GFc\\lF^^nFg\\l-F
h[l6$7&Fd^n7$$\"+++](o*Fc\\lFa[l7$F^_n$\"+)\\d^x#Fc\\lFg^nFi]l-Fh[l6$7
&F]_n7$$\"+++vV)*Fc\\lFa[l7$Fg_n$\"+^p&=t#Fc\\lF`_nFg\\l-Fh[l6$7&Ff_n7
$$\"+++++5!\"*Fa[l7$F``n$\"+9UT*o#Fc\\lFi_nFi]l-%+AXESLABELSG6$Q\"x6\"
Q!Fj`n-%%VIEWG6$;$F`[lF`[l$\"#7F`[l%(DEFAULTG" 1 2 0 1 10 0 2 9 1 4 2
1.000000 45.000000 45.000000 0 0 "Curve 1" "Curve 2" "Curve 3" "Curve \+
4" "Curve 5" "Curve 6" "Curve 7" "Curve 8" "Curve 9" "Curve 10" "Curve
11" "Curve 12" "Curve 13" "Curve 14" "Curve 15" "Curve 16" "Curve 17
" "Curve 18" "Curve 19" "Curve 20" "Curve 21" "Curve 22" "Curve 23" "C
urve 24" "Curve 25" "Curve 26" "Curve 27" "Curve 28" "Curve 29" "Curve
30" "Curve 31" "Curve 32" "Curve 33" "Curve 34" "Curve 35" "Curve 36
" "Curve 37" "Curve 38" "Curve 39" "Curve 40" "Curve 41" "Curve 42" "C
urve 43" "Curve 44" "Curve 45" "Curve 46" "Curve 47" "Curve 48" "Curve
49" "Curve 50" "Curve 51" "Curve 52" "Curve 53" "Curve 54" "Curve 55
" "Curve 56" "Curve 57" "Curve 58" "Curve 59" "Curve 60" "Curve 61" "C
urve 62" "Curve 63" "Curve 64" "Curve 65" }}}}{PARA 0 "" 0 "" {TEXT
-1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 49 "trap64 := trap(1/(
x+exp(x)),x=0..1,intervals=64);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%'
trap64G$\"+)yfL;&!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0
"" {TEXT -1 95 "A value which is accurate to 10 digits can be obtained
using Maple's numerical integration via " }{TEXT 0 9 "evalf/Int" }
{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> "
0 "" {MPLTEXT 1 0 53 "Int(1/(x+exp(x)),x=0..1);\narea := evalf(evalf(%
,15));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$IntG6$*&\"\"\"F',&%\"xGF'
-%$expG6#F)F'!\"\"/F);\"\"!F'" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%ar
eaG$\"+Mw+j^!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 ""
{TEXT -1 104 "The absolute error in the approximate value for the inte
gral obtained using 64 intervals is about 3.5e-5" }{XPPEDIT 18 0 "`` =
3.5*`.`*10^(-5);" "6#/%!G*(-%&FloatG6$\"#N!\"\"\"\"\"%\".GF+)\"#5,$\"
\"&F*F+" }{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "abserr64 := abs(trap64-area);" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#>%)abserr64G$\"'a@N!#5" }}}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 ""
}}{PARA 0 "" 0 "" {TEXT -1 198 "Assuming that the absolute error is pr
oportional to the square of the width of the intervals used, we can es
timate how many intervals will be needed to obtain a value which is co
rrect to 10 digits. " }}{PARA 0 "" 0 "" {TEXT -1 30 "If we aim for a t
olerance of " }{XPPEDIT 18 0 "epsilon = 2*`.`*10^(-11);" "6#/%(epsilo
nG*(\"\"#\"\"\"%\".GF')\"#5,$\"#6!\"\"F'" }{TEXT -1 95 ", this is unli
kely to affect the last decimal place, since a unit in the last place \+
(1 ulp) is " }{XPPEDIT 18 0 "10^(-10)" "6#)\"#5,$F$!\"\"" }{TEXT -1 2
". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 47 "eps := 2e-11;\nabserr64/eps;\nevalf(log[4](%),6);" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#>%$epsG$\"\"#!#6" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6#$\"+++xg " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0
"" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 2 " " }{XPPEDIT 18 0 "log
[4](1760770)" "6#-&%$logG6#\"\"%6#\"(q2w\"" }{TEXT -1 1 " " }{TEXT
300 1 "~" }{TEXT -1 28 " 10.3739 means that 1760770 " }{TEXT 299 1 "~
" }{TEXT -1 1 " " }{XPPEDIT 18 0 "4^10.3739" "6#)\"\"%-%&FloatG6$\"'RP
5!\"%" }{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 ""
0 "" {TEXT -1 89 "The desired tolerance is reached when the absolute e
rror is divided by 4 about 10 times. " }}{PARA 0 "" 0 "" {TEXT -1 70 "
Thus we should double the number of intervals 10 times to reach about \+
" }{XPPEDIT 18 0 "64*`.`*2^10 = 2^16;" "6#/*(\"#k\"\"\"%\".GF&\"\"#\"#
5*$F(\"#;" }{XPPEDIT 18 0 "``=65536" "6#/%!G\"&Ob'" }{TEXT -1 12 " int
ervals. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1
207 "The following calculations give progressively more accurate value
s for the integral by using the trapezoidal rule with a progressively \+
larger number of intervals - doubling the number of intervals each tim
e." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 43 "2^7;\ntrap(1/(x+exp(x)),x=0..1,intervals=%);" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#\"$G\"" }}{PARA 11 "" 1 "" {XPPMATH
20 "6#$\"+yc4j^!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0
"> " 0 "" {MPLTEXT 1 0 43 "2^8;\ntrap(1/(x+exp(x)),x=0..1,intervals=%)
;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#\"$c#" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6#$\"+X'HI;&!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 43 "2^9;\ntrap(1/(x+exp(x)),x=0.
.1,intervals=%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#\"$7&" }}{PARA 11
"" 1 "" {XPPMATH 20 "6#$\"+PJ,j^!#5" }}}{PARA 0 "" 0 "" {TEXT 298 1 " \+
" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 44 "2^10;\ntrap(1/(x+exp(x))
,x=0..1,intervals=%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#\"%C5" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+4!4I;&!#5" }}}{PARA 0 "" 0 ""
{TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 44 "2^11;\ntrap(
1/(x+exp(x)),x=0..1,intervals=%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#
\"%[?" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+yz+j^!#5" }}}{PARA 0 ""
0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 44 "2^12;\n
trap(1/(x+exp(x)),x=0..1,intervals=%);" }}{PARA 11 "" 1 "" {XPPMATH
20 "6#\"%'4%" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+?x+j^!#5" }}}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
44 "2^13;\ntrap(1/(x+exp(x)),x=0..1,intervals=%);" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6#\"%#>)" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+bw+j^!#5
" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 44 "2^14;\ntrap(1/(x+exp(x)),x=0..1,intervals=%);" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#\"&%Q;" }}{PARA 11 "" 1 "" {XPPMATH
20 "6#$\"+Rw+j^!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0
"> " 0 "" {MPLTEXT 1 0 44 "2^15;\ntrap(1/(x+exp(x)),x=0..1,intervals=%
);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#\"&oF$" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6#$\"+Nw+j^!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 44 "2^16;\ntrap(1/(x+exp(x)),x=0
..1,intervals=%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#\"&Ob'" }}{PARA
11 "" 1 "" {XPPMATH 20 "6#$\"+Mw+j^!#5" }}}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 ""
{TEXT -1 53 "This process can be automated by using the procedure " }
{TEXT 0 4 "trap" }{TEXT -1 18 " with the option \"" }{TEXT 281 12 "ite
rate=true" }{TEXT -1 2 "\"." }}{PARA 0 "" 0 "" {TEXT -1 73 "The end re
sult is a value for the integral which is correct to 10 digits." }}
{PARA 0 "" 0 "" {TEXT -1 1 " " }}{PARA 0 "" 0 "" {TEXT 265 4 "Note" }
{TEXT -1 10 ": This is " }{TEXT 265 16 "very inefficient" }{TEXT -1
132 " because of the large number of evaluations of the integrand need
ed, but the calculation is completed quickly because the procedure " }
{TEXT 0 4 "trap" }{TEXT -1 40 " performs most of the calculation using
" }{TEXT 265 34 "hardware floating point arithmetic" }{TEXT -1 2 ". \+
" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT
1 0 49 "trap(1/(x+exp(x)),x=0..1,iterate=true,info=true);" }}{PARA 11
"" 1 "" {XPPMATH 20 "6$%Fapproximation~with~1~interval~--->~~~G$\"0)*
\\o52ZM'!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Gapproximation~with~2~
intervals~--->~~~G$\"0+9'H*=$*\\&!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "
6$%Gapproximation~with~4~intervals~--->~~~G$\"039BH]8D&!#:" }}{PARA
11 "" 1 "" {XPPMATH 20 "6$%Gapproximation~with~8~intervals~--->~~~G$\"
0o*p&*oU&=&!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Happroximation~with
~16~intervals~--->~~~G$\"0*R+F\\jo^!#:" }}{PARA 11 "" 1 "" {XPPMATH
20 "6$%Happroximation~with~32~intervals~--->~~~G$\"0ZU<*eTk^!#:" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6$%Happroximation~with~64~intervals~--->
~~~G$\"0[i$)yfL;&!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Iapproximatio
n~with~128~intervals~--->~~~G$\"0%4+yc4j^!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Iapproximation~with~256~intervals~--->~~~G$\"0m?^kHI;&
!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Iapproximation~with~512~interv
als~--->~~~G$\"0%)pl88I;&!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Jappr
oximation~with~1024~intervals~--->~~~G$\"0Y6%4!4I;&!#:" }}{PARA 11 ""
1 "" {XPPMATH 20 "6$%Japproximation~with~2048~intervals~--->~~~G$\"0c?
w(z+j^!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Japproximation~with~4096
~intervals~--->~~~G$\"0vs'>x+j^!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$
%Japproximation~with~8192~intervals~--->~~~G$\"0#e=bw+j^!#:" }}{PARA
11 "" 1 "" {XPPMATH 20 "6$%Kapproximation~with~16384~intervals~--->~~~
G$\"03k!Rw+j^!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Kapproximation~wi
th~32768~intervals~--->~~~G$\"0jL]j2I;&!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Kapproximation~with~65536~intervals~--->~~~G$\"0-ESj2I
;&!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+Mw+j^!#5" }}}{PARA 0 ""
0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}
{SECT 1 {PARA 4 "" 0 "" {TEXT -1 10 "Example 7 " }{TEXT 289 44 ".. a t
ough example for numerical integration" }{TEXT -1 1 " " }}{PARA 0 ""
0 "" {TEXT -1 29 "We find an approximation for " }{XPPEDIT 18 0 "Int(s
qrt(1-x^2),x = 0 .. 1)" "6#-%$IntG6$-%%sqrtG6#,&\"\"\"F**$%\"xG\"\"#!
\"\"/F,;\"\"!F*" }{TEXT -1 46 " using the trapezoidal rule with 32 int
ervals." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 94 "drawtrap(sqrt(1-x^2),x=0..1,intervals=32,\n \+
scheme=stripes,scaling=constrained);" }}{PARA 13 "" 1 ""
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+++]()Fi]lF(7$F`]m$\"+$=H7%[Fi]lFi\\mF[_l-F^]l6$7&F_]m7$$\"+++]i!*Fi]l
F(7$Fi]m$\"+V;UFUFi]lFb]mFj]l-F^]l6$7&Fh]m7$$Fb_lFi]lF(7$Fb^m$\"+FF&)z
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Fj_m-%(SCALINGG6#%,CONSTRAINEDG-%%VIEWG6$;F(F*%(DEFAULTG" 1 2 0 1 10
0 2 9 1 4 1 1.000000 45.000000 45.000000 0 0 "Curve 1" "Curve 2" "Curv
e 3" "Curve 4" "Curve 5" "Curve 6" "Curve 7" "Curve 8" "Curve 9" "Curv
e 10" "Curve 11" "Curve 12" "Curve 13" "Curve 14" "Curve 15" "Curve 16
" "Curve 17" "Curve 18" "Curve 19" "Curve 20" "Curve 21" "Curve 22" "C
urve 23" "Curve 24" "Curve 25" "Curve 26" "Curve 27" "Curve 28" "Curve
29" "Curve 30" "Curve 31" "Curve 32" "Curve 33" }}}}{PARA 0 "" 0 ""
{TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 72 "student[trap
ezoid](sqrt(1-x^2),x=0..1,32);\ntrap32 := evalf(evalf(%,15));" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#,\"\"\"\"#kF%*F%\"#KF%-%$SumG6$*$,
&F%F%*&\"%C5!\"\"%\"iG\"\"#F1#F%F3/F2;F%\"#JF%F%" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6#>%'trap32G$\"+dgvPy!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "
" }}{PARA 0 "" 0 "" {TEXT -1 51 "The same result can be obtained with \+
the procedure " }{TEXT 0 4 "trap" }{TEXT -1 2 ". " }}{PARA 0 "" 0 ""
{TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 38 "trap(sqrt(1-
x^2),x=0..1,intervals=32);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+dgvP
y!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 133
"We can obtain a numerical value for this integral which is accurate t
o about 10 digits by first evaluating the integral analytically." }}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
62 "Int(sqrt(1-x^2),x=0..1);\nvalue(%);\narea := evalf(evalf(%,13));"
}}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$IntG6$*$,&\"\"\"F(*$)%\"xG\"\"#F(
!\"\"#F(F,/F+;\"\"!F(" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#,$*&\"\"%!\"
\"%#PiG\"\"\"F(" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%areaG$\"+M;)R&y!
#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 4 "The
" }{TEXT 265 14 "absolute error" }{TEXT -1 97 " in the value for the \+
integral obtained by using the trapezoidal rule with 32 intervals is .
. . " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 27 "abserr := abs(trap32-area);" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6#>%'abserrG$\")ybA;!#5" }}}{PARA 0 "" 0 "" {TEXT -1 15 "
. . . and the " }{TEXT 265 14 "relative error" }{TEXT -1 10 " is . . \+
. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 27 "relerr := abserr/abs(area);" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6#>%'relerrG$\"+aZ!f1#!#7" }}}{PARA 0 "" 0 "" {TEXT -1 0
"" }}{PARA 0 "" 0 "" {TEXT -1 27 " . . . which is about 0.2%." }}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 26 "The trape
zoidal rule does " }{TEXT 265 29 "not give a very good estimate" }
{TEXT -1 206 " for the integral in this case, even though we have used
a reasonably large number of intervals. The problem occurs towards th
e right end of the interval where the gradient of the curve approaches
infinity." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT
-1 65 "The error can be made small by using a very number of intervals
. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 80 "bigtrap := trap(sqrt(1-x^2),x=0..1,intervals=2^16);\n
abserr := abs(bigtrap-area);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%(big
trapG$\"+f9)R&y!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%'abserrG$\"$w
\"!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 3 "
If " }{TEXT 0 18 "student[trapezoid]" }{TEXT -1 20 " is used instead o
f " }{TEXT 0 4 "trap" }{TEXT -1 32 ", the computation takes longer. "
}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1
0 51 "evalf(student[trapezoid](sqrt(1-x^2),x=0..1,2^16));" }}{PARA 11
"" 1 "" {XPPMATH 20 "6#$\"+e9)R&y!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "
" }}{PARA 0 "" 0 "" {TEXT -1 52 "The calculation can be performed more
speedily with " }{TEXT 0 18 "student[trapezoid]" }{TEXT -1 10 " by us
ing " }{TEXT 0 6 "evalhf" }{TEXT -1 98 " after the symbolic expression
is constructed. This enables the calculation to be performed using "
}{TEXT 265 34 "hardware floating point arithmetic" }{TEXT -1 2 ". " }}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
65 "student[trapezoid](sqrt(1-x^2),x=0..1,2^16);\nevalhf(%);\nevalf(%)
;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#,\"\"\"\"'s58F%*F%\"&Ob'F%-%$
SumG6$*$,&F%F%*&\"+'Hn\\H%!\"\"%\"iG\"\"#F1#F%F3/F2;F%\"&Nb'F%F%" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"3U)fR(e9)R&y!#=" }}{PARA 11 "" 1 "
" {XPPMATH 20 "6#$\"+f9)R&y!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}
{PARA 0 "" 0 "" {TEXT 265 4 "Note" }{TEXT -1 28 ": It is not possible \+
to use " }{TEXT 0 6 "evalhf" }{TEXT -1 15 " composed with " }{TEXT 0
18 "student[trapezoid]" }{TEXT -1 10 " directly." }}{PARA 0 "" 0 ""
{TEXT -1 1 " " }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 52 "evalhf(stud
ent[trapezoid](sqrt(1-x^2),x=0..1,2^16));" }}{PARA 8 "" 1 "" {TEXT -1
66 "Error, unable to evaluate function `student[trapezoid]` in evalhf
\n" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 14 "Th
e procedure " }{TEXT 0 4 "trap" }{TEXT -1 18 " with the option \"" }
{TEXT 281 12 "iterate=true" }{TEXT -1 148 "\" manages to obtain a valu
e which is correct to 10 digits provided that the allowed maximum numb
er of iterations is increased to 23 via the option \"" }{TEXT 281 16 "
maxiterations=23" }{TEXT -1 6 "\" or \"" }{TEXT 281 10 "maxiter=23" }
{TEXT -1 3 "\". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> \+
" 0 "" {MPLTEXT 1 0 65 "trap(sqrt(1-x^2),x=0..1,iterate=true,maxiterat
ions=23,info=true);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Fapproximation
~with~1~interval~--->~~~G$\"0+++++++&!#:" }}{PARA 11 "" 1 "" {XPPMATH
20 "6$%Gapproximation~with~2~intervals~--->~~~G$\"0?A*=q7Io!#:" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6$%Gapproximation~with~4~intervals~--->~
~~G$\"05c-ns#*[(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Gapproximation
~with~8~intervals~--->~~~G$\"0%H*3'yaCx!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Happroximation~with~16~intervals~--->~~~G$\"0QpXfK\"3y
!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Happroximation~with~32~interva
ls~--->~~~G$\"0%G>dgvPy!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Happrox
imation~with~64~intervals~--->~~~G$\"0A\\>GU#[y!#:" }}{PARA 11 "" 1 "
" {XPPMATH 20 "6$%Iapproximation~with~128~intervals~--->~~~G$\"0c\"*4)
>&>&y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Iapproximation~with~256~i
ntervals~--->~~~G$\"04$RdRE`y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%I
approximation~with~512~intervals~--->~~~G$\"09*z\")ys`y!#:" }}{PARA
11 "" 1 "" {XPPMATH 20 "6$%Japproximation~with~1024~intervals~--->~~~G
$\"0bZj\">*Q&y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Japproximation~w
ith~2048~intervals~--->~~~G$\"0hGN\"*\\R&y!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Japproximation~with~4096~intervals~--->~~~G$\"0Q>!>/(R
&y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Japproximation~with~8192~int
ervals~--->~~~G$\"0Cu)ow(R&y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Ka
pproximation~with~16384~intervals~--->~~~G$\"0B(4K-)R&y!#:" }}{PARA
11 "" 1 "" {XPPMATH 20 "6$%Kapproximation~with~32768~intervals~--->~~~
G$\"0aN$Q6)R&y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Kapproximation~w
ith~65536~intervals~--->~~~G$\"0eR(e9)R&y!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Lapproximation~with~131072~intervals~--->~~~G$\"0e>?d
\")R&y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Lapproximation~with~2621
44~intervals~--->~~~G$\"07q?h\")R&y!#:" }}{PARA 11 "" 1 "" {XPPMATH
20 "6$%Lapproximation~with~524288~intervals~--->~~~G$\"08Iii\")R&y!#:
" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Mapproximation~with~1048576~inter
vals~--->~~~G$\"0WO7j\")R&y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Map
proximation~with~2097152~intervals~--->~~~G$\"0[1Ij\")R&y!#:" }}{PARA
11 "" 1 "" {XPPMATH 20 "6$%Mapproximation~with~4194304~intervals~--->~
~~G$\"0EKOj\")R&y!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Mapproximatio
n~with~8388608~intervals~--->~~~G$\"0P`Qj\")R&y!#:" }}{PARA 11 "" 1 "
" {XPPMATH 20 "6#$\"+M;)R&y!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4 "" 0 "
" {TEXT -1 10 "Example 8 " }{TEXT 305 124 ".. estimating the error by \+
doubling the number of intervals used instead of calculating an accura
te value by another method " }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
1 ";" }}}{PARA 0 "" 0 "" {TEXT 265 4 "Note" }{TEXT -1 15 ": Suppose th
at " }{XPPEDIT 18 0 "I[1]" "6#&%\"IG6#\"\"\"" }{TEXT -1 5 " and " }
{XPPEDIT 18 0 "I[2]" "6#&%\"IG6#\"\"#" }{TEXT -1 53 " are trapezoidal \+
rule approximations for an integral " }{XPPEDIT 18 0 "I=Int(f(x),x=a..
b)" "6#/%\"IG-%$IntG6$-%\"fG6#%\"xG/F+;%\"aG%\"bG" }{TEXT -1 16 " obta
ined using " }{TEXT 313 1 "n" }{TEXT -1 5 " and " }{XPPEDIT 18 0 "2*n
" "6#*&\"\"#\"\"\"%\"nGF%" }{TEXT -1 29 " intervals respectively. Let \+
" }{XPPEDIT 18 0 "e[1]" "6#&%\"eG6#\"\"\"" }{TEXT -1 5 " and " }
{XPPEDIT 18 0 "e[2]" "6#&%\"eG6#\"\"#" }{TEXT -1 48 " be the correspon
ding absolute errors, that is, " }{XPPEDIT 18 0 "e[1]=abs(I[1]-I)" "6#
/&%\"eG6#\"\"\"-%$absG6#,&&%\"IG6#F'F'F-!\"\"" }{TEXT -1 5 " and " }
{XPPEDIT 18 0 "e[2]=abs(I[2]-I)" "6#/&%\"eG6#\"\"#-%$absG6#,&&%\"IG6#F
'\"\"\"F-!\"\"" }{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 76 "An ear
lier example suggests that the error is approximately proportional to \+
" }{XPPEDIT 18 0 "h^2" "6#*$%\"hG\"\"#" }{TEXT -1 18 ". This means tha
t " }{XPPEDIT 18 0 "e[1]" "6#&%\"eG6#\"\"\"" }{TEXT -1 1 " " }{TEXT
317 1 "~" }{TEXT -1 1 " " }{XPPEDIT 18 0 "4*e[2]" "6#*&\"\"%\"\"\"&%\"
eG6#\"\"#F%" }{TEXT -1 6 " and " }{XPPEDIT 18 0 "I[1]" "6#&%\"IG6#\"
\"\"" }{TEXT -1 5 " and " }{XPPEDIT 18 0 "I[2]" "6#&%\"IG6#\"\"#" }
{TEXT -1 25 " are on the same side of " }{TEXT 315 1 "I" }{TEXT -1 11
", that is, " }{XPPEDIT 18 0 "I[1]F-F6FA-F$6&7$F*7$F+F>F-F6FA-F$6%7$F'7$F($!\"\"F)-F.6&F0F)F)F)-%*
LINESTYLEGF8-F$6%7$FH7$FI$!3++++++++]F@FVFX-F$6%7$F*7$F+FTFVFX-F$6'7$7
$$\"$v#!\"#$!\"$FU7$F(Feo7%7$$\"*+++5\"!\"*$!++++]O!#5Fgo7$Fjo$!++++]B
F_p-FB6#%,PATCHNOGRIDG-F.6&F0$\")#)eqkF3$\"))eqk\"F3Fjp-FY6#\"\"$-F$6'
7$7$$\"$D$FdoFeo7$$\"$+'FdoFeo7%7$$\"++++!*eF\\pFapFeq7$FjqF]pFcpFfpF
\\q-F$6'7$7$$\"#oFUFeo7$$\"#gFUFeo7%7$$\"++++'4'F\\pF]pFcr7$FhrFapFcpF
fpF\\q-F$6'7$7$$\"#sFUFeo7$$\"#!)FUFeo7%7$$\"++++/zF\\pFapFas7$FfsF]pF
cpFfpF\\q-F$6'7$7$$\"#QFU$F3FU7$F(F_t7%7$$\"*+++9\"F\\p$!++++]')F_pF`t
7$Fct$!++++]tF_pFcpFfpF\\q-F$6'7$7$$\"#UFUF_t7$FbsF_t7%7$$\"++++')yF\\
pFhtF`u7$FcuFetFcpFfpF\\q-%%TEXTG6%7$F($F,FUQ\"I6\"-%%FONTG6%%&TIMESG%
&ROMANG\"#7-Fgu6%7$FIFjuF[vF]v-Fgu6%7$F+FjuF[vF]v-Fgu6%7$$F^qF)FeoQ$3~
eF\\v-F^v6$%*HELVETICAG\"#5-Fgu6%7$$\"\"(F)FeoQ\"eF\\vF^w-Fgu6%7$$\"\"
%F)$!#wFdoFgwF^w-Fgu6%7$$\"#TFU$F\\pFUQ\"1F\\v-F^v6$F`wF,-Fgu6%7$$F,Fd
o$FfwFUFexFfx-Fgu6%7$$\"$3'FdoF\\yQ\"2F\\vFfx-Fgu6%7$$\"$=$Fdo$!\"%FUF
byFfx-Fgu6%7$$\"#rFUFhyFbyFfx-%*AXESSTYLEG6#%%NONEG-%+AXESLABELSG6%Q!F
\\vFfz-F^v6#%(DEFAULTG-%%VIEWG6$;F(F+;FT$\"\"\"F)" 1 2 0 1 10 0 2 9 1
1 2 1.000000 45.000000 45.000000 0 0 "Curve 1" "Curve 2" "Curve 3" "Cu
rve 4" "Curve 5" "Curve 6" "Curve 7" "Curve 8" "Curve 9" "Curve 10" "C
urve 11" "Curve 12" "Curve 13" "Curve 14" "Curve 15" "Curve 16" "Curve
17" "Curve 18" "Curve 19" "Curve 20" "Curve 21" "Curve 22" "Curve 23
" "Curve 24" }}{TEXT -1 3 " " }}{PARA 0 "" 0 "" {TEXT -1 17 "It foll
ows that " }{XPPEDIT 18 0 "abs(I[1]-I[2])" "6#-%$absG6#,&&%\"IG6#\"\"
\"F*&F(6#\"\"#!\"\"" }{TEXT -1 1 " " }{TEXT 316 1 "~" }{TEXT -1 1 " "
}{XPPEDIT 18 0 "3*e[2]" "6#*&\"\"$\"\"\"&%\"eG6#\"\"#F%" }{TEXT -1 21
", which implies that " }{XPPEDIT 18 0 "e[2]" "6#&%\"eG6#\"\"#" }
{TEXT -1 1 " " }{TEXT 314 1 "~" }{TEXT -1 1 " " }{XPPEDIT 18 0 "abs(I[
1]-I[2])/3" "6#*&-%$absG6#,&&%\"IG6#\"\"\"F+&F)6#\"\"#!\"\"F+\"\"$F/"
}{TEXT -1 3 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 ""
{TEXT -1 27 "We find approximations for " }{XPPEDIT 18 0 "Int(1/(1+ln(
x+1)),x = 0 .. 1);" "6#-%$IntG6$*&\"\"\"F',&F'F'-%#lnG6#,&%\"xGF'F'F'F
'!\"\"/F-;\"\"!F'" }{TEXT -1 53 " using the trapezoidal rule with 32 a
nd 64 intervals." }}{PARA 0 "" 0 "" {TEXT -1 69 "The picture illustrat
es using the trapezoidal rule with 32 intervals." }}{PARA 0 "" 0 ""
{TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 127 "drawtrap(1/
(1+ln(x+1)),x=[0..1,-.1..1.2],intervals=32,\n scheme=stripes,co
lor=magenta,shading=[plum,COLOR(RGB,.7,1,.7)]);" }}{PARA 13 "" 1 ""
{GLPLOT2D 596 351 351 {PLOTDATA 2 "6E-%'CURVESG6%7S7$$!3/+++++++5!#=$
\"3g=A/&oox6\"!#<7$$!3uLLLe*pj;(!#>$\"39<&>*H]L!3\"F-7$$!3!pm;/hV3q%F1
$\"3adD#*[[e]5F-7$$!3hLL$3P,\"G>F1$\"3%>/%f(*e&)>5F-7$$\"3bsmmTS?I')!#
?$\"3\"o=_$o.![\"**F*7$$\"3PJLekk(3k$F1$\"3O)fG@6JZl*F*7$$\"3vlm\"Hi/j
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+++0UbxlF*$\"3D)yb\"=!oCk'F*7$$\"3k++DT3!*\\oF*$\"3K5lRO)R8d'F*7$$\"34
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j%R?)F*$\"3S*3>j?+PD'F*7$$\"3M,+]-W-#[)F*$\"3M8v'F*7$$\"3uK$e*=
UnV()F*$\"3+`DAhH[ThF*7$$\"3V,]7oO<7
M)*F*$\"3'oxP,vc`$fF*7$$\"3rm;/GT)4,\"F-$\"3'eMxvG=*z&F*7$$\"3AL$3
U(3D#4\"F-$\"39;KX')R%Hv&F*7$$\"3cmmm4u+=6F-$\"3d0oY\"oKFr&F*7$$\"3)**
\\i&[#pa9\"F-$\"3k`%e[B(*4n&F*7$$\"3-+vVKPvr6F-$\"3$pe>A@0@j&F*7$$\"3%
**************>\"F-$\"3QMLy64T\"f&F*-%'COLOURG6&%$RGBG$\"*++++\"!\")$
\"\"!Fb[lF^[l-%*THICKNESSG6#\"\"#-%)POLYGONSG6$7&7$Fa[lFa[l7$$\"++++DJ
!#6Fa[l7$F]\\l$\"+$op9q*!#57$Fa[l$\"\"\"Fb[l-F[[l6&F][l$\")1Zw\"*F`[l$
\")PJ%y'F`[lFi\\l-Fh[l6$7&F\\\\l7$$\"++++]iF_\\lFa[l7$Fa]l$\"+CkSG%*Fc
\\lF`\\l-%&COLORG6&F][l$\"\"(!\"\"Ff\\lFi]l-Fh[l6$7&F`]l7$$\"++++v$*F_
\\lFa[l7$F`^l$\"+pudx\"*Fc\\lFc]lFg\\l-Fh[l6$7&F_^l7$$\"++++]7Fc\\lFa[
l7$Fi^l$\"+$)*zi%*)Fc\\lFb^lFf]l-Fh[l6$7&Fh^l7$$\"+++]i:Fc\\lFa[l7$Fb_
l$\"+sjBK()Fc\\lF[_lFg\\l-Fh[l6$7&Fa_l7$$\"++++v=Fc\\lFa[l7$F[`l$\"+5N
^L&)Fc\\lFd_lFf]l-Fh[l6$7&Fj_l7$$\"+++](=#Fc\\lFa[l7$Fd`l$\"+[(f%[$)Fc
\\lF]`lFg\\l-Fh[l6$7&Fc`l7$$\"+++++DFc\\lFa[l7$F]al$\"+b_lv\")Fc\\lFf`
lFf]l-Fh[l6$7&F\\al7$$\"+++]7GFc\\lFa[l7$Ffal$\"+lD(Q,)Fc\\lF_alFg\\l-
Fh[l6$7&Feal7$$F^\\lFc\\lFa[l7$F_bl$\"+7\\/iyFc\\lFhalFf]l-Fh[l6$7&F^b
l7$$\"+++]PMFc\\lFa[l7$Fgbl$\"+R1C>xFc\\lF`blFg\\l-Fh[l6$7&Ffbl7$$\"++
++]PFc\\lFa[l7$F`cl$\"+YBk%e(Fc\\lFiblFf]l-Fh[l6$7&F_cl7$$\"+++]iSFc\\
lFa[l7$Ficl$\"+8)HvX(Fc\\lFbclFg\\l-Fh[l6$7&Fhcl7$$\"++++vVFc\\lFa[l7$
Fbdl$\"+'*eEPtFc\\lF[dlFf]l-Fh[l6$7&Fadl7$$\"+++](o%Fc\\lFa[l7$F[el$\"
+8[GBsFc\\lFddlFg\\l-Fh[l6$7&Fjdl7$$\"+++++]Fc\\lFa[l7$Fdel$\"+iB3:rFc
\\lF]elFf]l-Fh[l6$7&Fcel7$$\"+++]7`Fc\\lFa[l7$F]fl$\"+gFc\\lFj\\mFf]l-Fh[l6$7&F`]m7$$\"+
++](o*Fc\\lFa[l7$Fi]m$\"+H9hhfFc\\lFb]mFg\\l-Fh[l6$7&Fh]m7$$\"+++++5!
\"*Fa[l7$Fb^m$\"+!4hh!fFc\\lF[^mFf]l-%+AXESLABELSG6$Q\"x6\"Q!F\\_m-%%V
IEWG6$;$F[^lF[^l$\"#7F[^l%(DEFAULTG" 1 2 0 1 10 0 2 9 1 4 2 1.000000
45.000000 45.000000 0 0 "Curve 1" "Curve 2" "Curve 3" "Curve 4" "Curve
5" "Curve 6" "Curve 7" "Curve 8" "Curve 9" "Curve 10" "Curve 11" "Cur
ve 12" "Curve 13" "Curve 14" "Curve 15" "Curve 16" "Curve 17" "Curve 1
8" "Curve 19" "Curve 20" "Curve 21" "Curve 22" "Curve 23" "Curve 24" "
Curve 25" "Curve 26" "Curve 27" "Curve 28" "Curve 29" "Curve 30" "Curv
e 31" "Curve 32" "Curve 33" }}}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 101 "trap32 := trap(1/(1+ln(x+1)
),x=0..1,intervals=32);\ntrap64 := trap(1/(1+ln(x+1)),x=0..1,intervals
=64);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%'trap32G$\"+z(yAP(!#5" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#>%'trap64G$\"+^]xrt!#5" }}}{PARA 0 ""
0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 33 "Next we calculate th
e difference " }{XPPEDIT 18 0 "delta;" "6#%&deltaG" }{TEXT -1 47 " bet
ween these two trapezoidal rule estimates. " }}{PARA 0 "" 0 "" {TEXT
-1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 28 "delta := abs(trap3
2-trap64);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%&deltaG$\"'GP]!#5" }}}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 105 "Using th
e note above, this gives an approximate upper bound for the error in t
he 64 interval estimate of " }{XPPEDIT 18 0 "1/3" "6#*&\"\"\"F$\"\"$!
\"\"" }{TEXT -1 18 " ( 0.0000503728 ) " }{TEXT 308 1 "~" }{TEXT -1 15
" 0.0000167909. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> \+
" 0 "" {MPLTEXT 1 0 39 "abserr64_estimate := evalf[6](delta/3);" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#>%2abserr64_estimateG$\"'4z;!#5" }}}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 95 "A value w
hich is accurate to 10 digits can be obtained using Maple's numerical \+
integration via " }{TEXT 0 9 "evalf/Int" }{TEXT -1 2 ". " }}{PARA 0 "
" 0 "" {TEXT -1 116 "This value can be used to calculate the actual er
ror in the 64 interval trapezoidal rule estimate for the integral. " }
}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1
0 85 "Int(1/(1+ln(x+1)),x=0..1);\narea := evalf[14](evalf(%));\nabserr
64 := abs(trap64-area);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$IntG6$*&
\"\"\"F',&F'F'-%#lnG6#,&%\"xGF'F'F'F'!\"\"/F-;\"\"!F'" }}{PARA 11 ""
1 "" {XPPMATH 20 "6#>%%areaG$\"/oB'42;P(!#9" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6#>%)abserr64G$\"'bz;!#5" }}}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 ""
{TEXT -1 112 "The absolute error in the approximate value for the inte
gral obtained using 64 intervals is about 0.0000167955. " }}{PARA 0 "
" 0 "" {TEXT -1 209 "The error estimate calculated previously, without
reference to the accurate value, agrees well with the actual error. N
ote that both trapezoidal rule estimates are greater than the true val
ue of the integral. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "
" {TEXT -1 225 "Either the error estimate, or the actual error in the \+
64 interval trapezoidal estimate could be used to predict the approxim
ate number of intervals needed to obtain a trapezoidal rule estimate w
hich is correct to 10 digits. " }}{PARA 0 "" 0 "" {TEXT -1 30 "If we \+
aim for a tolerance of " }{XPPEDIT 18 0 "epsilon = 2*`.`*10^(-11);" "
6#/%(epsilonG*(\"\"#\"\"\"%\".GF')\"#5,$\"#6!\"\"F'" }{TEXT -1 95 ", t
his is unlikely to affect the last decimal place, since a unit in the \+
last place (1 ulp) is " }{XPPEDIT 18 0 "10^(-10)" "6#)\"#5,$F$!\"\"" }
{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> "
0 "" {MPLTEXT 1 0 48 "eps := 2e-11;\nabserr64/eps;\nevalf[6](log[4](%)
);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%$epsG$\"\"#!#6" }}{PARA 11 ""
1 "" {XPPMATH 20 "6#$\"+++v(R)!\"%" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#
$\"'#)R)*!\"&" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 2 " " }
{XPPEDIT 18 0 "log[4]( 839775 )" "6#-&%$logG6#\"\"%6#\"'v(R)" }{TEXT
-1 1 " " }{TEXT 307 1 "~" }{TEXT -1 27 " 9.83982 means that 839775 " }
{TEXT 306 1 "~" }{TEXT -1 1 " " }{XPPEDIT 18 0 "4^9.83982" "6#)\"\"%-%
&FloatG6$\"'#)R)*!\"&" }{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "
" }}{PARA 0 "" 0 "" {TEXT -1 89 "The desired tolerance is reached when
the absolute error is divided by 4 about 10 times. " }}{PARA 0 "" 0 "
" {TEXT -1 70 "Thus we should double the number of intervals 10 times \+
to reach about " }{XPPEDIT 18 0 "64*`.`*2^10 = 2^16;" "6#/*(\"#k\"\"\"
%\".GF&\"\"#\"#5*$F(\"#;" }{XPPEDIT 18 0 "``=65536" "6#/%!G\"&Ob'" }
{TEXT -1 12 " intervals. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "
" 0 "" {TEXT -1 53 "This process can be automated by using the procedu
re " }{TEXT 0 4 "trap" }{TEXT -1 18 " with the option \"" }{TEXT 281
12 "iterate=true" }{TEXT -1 2 "\"." }}{PARA 0 "" 0 "" {TEXT -1 73 "The
end result is a value for the integral which is correct to 10 digits.
" }}{PARA 0 "" 0 "" {TEXT -1 1 " " }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 50 "trap(1/(1+ln(x+1)),x=0..1,iterate=true,info=true);" }
}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Fapproximation~with~1~interval~--->~
~~G$\"0A[da!3`z!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Gapproximation~
with~2~intervals~--->~~~G$\"0N![`93Mv!#:" }}{PARA 11 "" 1 "" {XPPMATH
20 "6$%Gapproximation~with~4~intervals~--->~~~G$\"0ve[V8RT(!#:" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6$%Gapproximation~with~8~intervals~--->~
~~G$\"0hDTT6BQ(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Happroximation~
with~16~intervals~--->~~~G$\"0QN(o;Hut!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Happroximation~with~32~intervals~--->~~~G$\"0vy#z(yAP(
!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Happroximation~with~64~interva
ls~--->~~~G$\"0\"**)30v~~~G$\"0q?q3\\;P(!#:" }}{PARA 11 ""
1 "" {XPPMATH 20 "6$%Iapproximation~with~256~intervals~--->~~~G$\"0NlS
f<;P(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Iapproximation~with~512~i
ntervals~--->~~~G$\"0B-2s4;P(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%J
approximation~with~1024~intervals~--->~~~G$\"0n`Bv2;P(!#:" }}{PARA 11
"" 1 "" {XPPMATH 20 "6$%Japproximation~with~2048~intervals~--->~~~G$\"
0-m-E2;P(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Japproximation~with~4
096~intervals~--->~~~G$\"04Ws82;P(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20
"6$%Japproximation~with~8192~intervals~--->~~~G$\"0h)[1rgrt!#:" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6$%Kapproximation~with~16384~intervals~-
-->~~~G$\"0u*z)42;P(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Kapproxima
tion~with~32768~intervals~--->~~~G$\"0`xo42;P(!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Kapproximation~with~65536~intervals~--->~~~G$\"0-(R'42
;P(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Lapproximation~with~131072~
intervals~--->~~~G$\"0(oF'42;P(!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#
$\"+'42;P(!#5" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> "
0 "" {MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 10 "Examp
le 9 " }{TEXT 288 53 ".. an example where the integrand has negative v
alues" }{TEXT -1 1 " " }}{PARA 0 "" 0 "" {TEXT -1 29 "We find an appro
ximation for " }{XPPEDIT 18 0 "Int(sin(x),x = 0 .. 3*Pi/2);" "6#-%$Int
G6$-%$sinG6#%\"xG/F);\"\"!*(\"\"$\"\"\"%#PiGF/\"\"#!\"\"" }{TEXT -1
46 " using the trapezoidal rule with 24 intervals." }}{PARA 0 "" 0 ""
{TEXT -1 40 "In this example the associated graph of " }{XPPEDIT 18 0
"y=sin(x)" "6#/%\"yG-%$sinG6#%\"xG" }{TEXT -1 29 " is both above and b
elow the " }{TEXT 287 1 "x" }{TEXT -1 60 " axis in different sections \+
of the interval of integration. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 52 "drawtrap(sin(x),x=[0..3*Pi/2
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{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
62 "student[trapezoid](sin(x),x=0..3*Pi/2,24);\ntrap24 := evalf(%);" }
}{PARA 11 "" 1 "" {XPPMATH 20 "6#,$*\"\"\"\"#KF&*&%#PiGF&,&F&!\"\"*&
\"\"#F&-%$SumG6$-%$sinG6#,$*(\"#;F+%\"iGF&F)F&F&/F7;F&\"#BF&F&F&F&F&"
}}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%'trap24G$\"+A<&y'**!#5" }}}{PARA
0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 39 "The exact value
for this integral is 1." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 42 "Int(sin(x),x=0..3*Pi/2);\narea := v
alue(%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$IntG6$-%$sinG6#%\"xG/F)
;\"\"!,$*(\"\"$\"\"\"\"\"#!\"\"%#PiGF0F0" }}{PARA 11 "" 1 "" {XPPMATH
20 "6#>%%areaG\"\"\"" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0
"" {TEXT -1 14 "The procedure " }{TEXT 0 4 "trap" }{TEXT -1 35 " gives
this value with the option \"" }{TEXT 281 12 "iterate=true" }{TEXT
-1 3 "\". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "
" {MPLTEXT 1 0 48 "trap(sin(x),x=0..3*Pi/2,iterate=true,info=true);" }
}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Fapproximation~with~1~interval~--->~
~~G$!0M#>!\\%>cB!#9" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Gapproximation
~with~2~intervals~--->~~~G$\"0AKrcQ)z[!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Gapproximation~with~4~intervals~--->~~~G$\"0Rc*Hct:))!
#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Gapproximation~with~8~intervals
~--->~~~G$\"0iB1Ol\"4(*!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Happrox
imation~with~16~intervals~--->~~~G$\"03eM83w#**!#:" }}{PARA 11 "" 1 "
" {XPPMATH 20 "6$%Happroximation~with~32~intervals~--->~~~G$\"0yM%z;#>
)**!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Happroximation~with~64~inte
rvals~--->~~~G$\"03g`k\"[&***!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%I
approximation~with~128~intervals~--->~~~G$\"0'o*y[q))***!#:" }}{PARA
11 "" 1 "" {XPPMATH 20 "6$%Iapproximation~with~256~intervals~--->~~~G$
\"0[eni<(****!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Iapproximation~wi
th~512~intervals~--->~~~G$\"0k))pSH*****!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Japproximation~with~1024~intervals~--->~~~G$\"0%fw^B)*
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{PARA 11 "" 1 "" {XPPMATH 20 "6$%Japproximation~with~8192~intervals~--
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ation~with~16384~intervals~--->~~~G$\"0sh5$********!#:" }}{PARA 11 ""
1 "" {XPPMATH 20 "6$%Kapproximation~with~32768~intervals~--->~~~G$\"0
\\lF)********!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Kapproximation~wi
th~65536~intervals~--->~~~G$\"0b\"p&*********!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Lapproximation~with~131072~intervals~--->~~~G$\"0+B*)*
********!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6$%Lapproximation~with~26
2144~intervals~--->~~~G$\"0tI(**********!#:" }}{PARA 11 "" 1 ""
{XPPMATH 20 "6$%Lapproximation~with~524288~intervals~--->~~~G$\"07L***
********!#:" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+++++5!\"*" }}}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
1 ";" }}}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}{PARA 0 ""
0 "" {TEXT -1 0 "" }}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 5 "Tasks" }}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{SECT 1 {PARA 4 "" 0 "
" {TEXT -1 2 "Q1" }}{PARA 0 "" 0 "" {TEXT -1 32 "(a) Find approximate \+
values for " }{XPPEDIT 18 0 "Int(1/(x+exp(x)),x = 0 .. 1);" "6#-%$IntG
6$*&\"\"\"F',&%\"xGF'-%$expG6#F)F'!\"\"/F);\"\"!F'" }{TEXT -1 53 " usi
ng the trapezoidal rule with 32 and 64 intervals." }}{PARA 0 "" 0 ""
{TEXT -1 73 "(b) Illustrate the approximation from (a) with 32 interva
ls graphically. " }}{PARA 0 "" 0 "" {TEXT -1 72 "(c) Calculate the def
inite integral in (a) by using the Maple procedure " }{TEXT 0 14 "eval
f(Int(..))" }{TEXT -1 94 ", and use this value to calculate the absolu
te error in each of the values found in part (a). " }}{PARA 0 "" 0 ""
{TEXT -1 188 "(d) Find the ratio of the absolute errors calculated in \+
(c) to verify experimentally that the trapezoidal rule has order 1, th
at is, the error is approximately proportional to the square, " }
{XPPEDIT 18 0 "h^2" "6#*$%\"hG\"\"#" }{TEXT -1 17 ", of the spacing "
}{TEXT 268 1 "h" }{TEXT -1 13 " between the " }{TEXT 278 1 "x" }{TEXT
-1 18 " values used (the " }{TEXT 265 9 "step-size" }{TEXT -1 2 ")." }
}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 265 4 "Note" }
{TEXT -1 112 ": The trapezoidal rule is designed to give exact answers
for polynomials of degree 1, that is, linear functions." }}{PARA 0 "
" 0 "" {TEXT -1 41 "_________________________________________" }}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 ">
" 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }
}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT
-1 41 "_________________________________________" }}{EXCHG {PARA 0 "> \+
" 0 "" {MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 2 "Q2"
}}{PARA 0 "" 0 "" {TEXT -1 32 "(a) Find approximate values for " }
{XPPEDIT 18 0 "Int(x^2*sqrt(arctan(x)),x = 0 .. 1);" "6#-%$IntG6$*&%\"
xG\"\"#-%%sqrtG6#-%'arctanG6#F'\"\"\"/F';\"\"!F/" }{TEXT -1 46 " using
the trapezoidal rule with 32 intervals." }}{PARA 0 "" 0 "" {TEXT -1
55 "(b) Illustrate the approximation from (a) graphically. " }}{PARA
0 "" 0 "" {TEXT -1 72 "(c) Calculate the definite integral in (a) by u
sing the Maple procedure " }{TEXT 0 14 "evalf(Int(..))" }{TEXT -1 86 "
, and use this value to calculate the absolute error in the value foun
d in part (a). " }}{PARA 0 "" 0 "" {TEXT -1 34 "(d) Find an approxima
te value for " }{XPPEDIT 18 0 "Int(x^2*sqrt(arctan(x)),x = 0 .. 1);" "
6#-%$IntG6$*&%\"xG\"\"#-%%sqrtG6#-%'arctanG6#F'\"\"\"/F';\"\"!F/" }
{TEXT -1 71 " which is correct to 10 digits using the trapezoidal rule
in two ways. " }}{PARA 15 "" 0 "" {TEXT -1 257 "(i) Calculate a numbe
r of approximations to the definite integral using the trapezoidal rul
e, with a progressively larger number of intervals, until there is no \+
change in the 10 digits of the result. It is convenient to double the \+
intervals with each step. " }}{PARA 15 "" 0 "" {TEXT -1 23 "(ii) Use t
he procedure " }{TEXT 0 4 "trap" }{TEXT -1 18 " with the option \"" }
{TEXT 281 12 "iterate=true" }{TEXT -1 3 "\". " }}{PARA 0 "" 0 ""
{TEXT -1 41 "_________________________________________" }}{PARA 0 ""
0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 ">
" 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 41 "__
_______________________________________" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 2 "Q3" }}
{PARA 0 "" 0 "" {TEXT -1 32 "(a) Find approximate values for " }
{XPPEDIT 18 0 "Int(ln(x^(2/3)+1),x = 0 .. 1);" "6#-%$IntG6$-%#lnG6#,&)
%\"xG*&\"\"#\"\"\"\"\"$!\"\"F.F.F./F+;\"\"!F." }{TEXT -1 46 " using th
e trapezoidal rule with 32 intervals." }}{PARA 0 "" 0 "" {TEXT -1 55 "
(b) Illustrate the approximation from (a) graphically. " }}{PARA 0 ""
0 "" {TEXT -1 72 "(c) Calculate the definite integral in (a) by using \+
the Maple procedure " }{TEXT 0 14 "evalf(Int(..))" }{TEXT -1 86 ", and
use this value to calculate the absolute error in the value found in \+
part (a). " }}{PARA 0 "" 0 "" {TEXT -1 34 "(d) Find an approximate va
lue for " }{XPPEDIT 18 0 "Int(ln(x^(2/3)+1),x = 0 .. 1);" "6#-%$IntG6$
-%#lnG6#,&)%\"xG*&\"\"#\"\"\"\"\"$!\"\"F.F.F./F+;\"\"!F." }{TEXT -1
71 " which is correct to 10 digits using the trapezoidal rule in two w
ays. " }}{PARA 15 "" 0 "" {TEXT -1 258 "(i) Calculate a number of appr
oximations for the definite integral using the trapezoidal rule, with \+
a progressively larger number of intervals, until there is no change i
n the 10 digits of the result. It is convenient to double the interval
s with each step. " }}{PARA 15 "" 0 "" {TEXT -1 23 "(ii) Use the proce
dure " }{TEXT 0 4 "trap" }{TEXT -1 18 " with the option \"" }{TEXT
281 12 "iterate=true" }{TEXT -1 3 "\". " }}{PARA 0 "" 0 "" {TEXT -1
96 "(d) Could you have predicted roughly how many intervals would be n
eeded to obtain the value for " }{XPPEDIT 18 0 "Int(ln(x^(2/3)+1),x = \+
0 .. 1);" "6#-%$IntG6$-%#lnG6#,&)%\"xG*&\"\"#\"\"\"\"\"$!\"\"F.F.F./F+
;\"\"!F." }{TEXT -1 27 " obtained in (d)? Explain. " }}{PARA 0 "" 0 "
" {TEXT -1 41 "_________________________________________" }}{PARA 0 "
" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 ">
" 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 41 "__
_______________________________________" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 2 "Q4" }}
{PARA 0 "" 0 "" {TEXT -1 31 " Find an approximate value for " }
{XPPEDIT 18 0 "Int(sin(x)/x,x = 0 .. 1);" "6#-%$IntG6$*&-%$sinG6#%\"xG
\"\"\"F*!\"\"/F*;\"\"!F+" }{TEXT -1 49 " correct to 10 digits using th
e trapezoidal rule." }}{PARA 0 "" 0 "" {TEXT 265 5 "Hints" }{TEXT -1
2 ": " }}{PARA 15 "" 0 "" {TEXT -1 43 "Replace the lower limit of the \+
integral by " }{XPPEDIT 18 0 "10^(-13);" "6#)\"#5,$\"#8!\"\"" }{TEXT
-1 132 " to avoid division by zero. This value will not affect the 1st
10 digits of the calculated approximations to the definite integral. \+
" }}{PARA 15 "" 0 "" {TEXT -1 183 "Calculate a number of approximation
s to the definite integral using the trapezoidal rule, with a progress
ively increasing number of intervals, until the first 10 digits stop c
hanging." }}{PARA 0 "" 0 "" {TEXT -1 41 "_____________________________
____________" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0
"" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA
0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT
-1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "
" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA
0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }
}}{PARA 0 "" 0 "" {TEXT -1 41 "_______________________________________
__" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4
"" 0 "" {TEXT -1 2 "Q5" }}{PARA 0 "" 0 "" {TEXT -1 32 "(a) Find approx
imate values for " }{XPPEDIT 18 0 "Int(x*sqrt(1-x^2),x = 0 .. 1/2);" "
6#-%$IntG6$*&%\"xG\"\"\"-%%sqrtG6#,&F(F(*$F'\"\"#!\"\"F(/F';\"\"!*&F(F
(F.F/" }{TEXT -1 5 " and " }{XPPEDIT 18 0 "Int(x*sqrt(1-x^2),x = 0 .. \+
1);" "6#-%$IntG6$*&%\"xG\"\"\"-%%sqrtG6#,&F(F(*$F'\"\"#!\"\"F(/F';\"\"
!F(" }{TEXT -1 46 " using the trapezoidal rule with 32 intervals." }}
{PARA 0 "" 0 "" {TEXT -1 46 "(b) Illustrate the approximation from (a)
for " }{XPPEDIT 18 0 "Int(x*sqrt(1-x^2),x = 0 .. 1)" "6#-%$IntG6$*&%
\"xG\"\"\"-%%sqrtG6#,&F(F(*$F'\"\"#!\"\"F(/F';\"\"!F(" }{TEXT -1 32 " \+
with 32 intervals graphically. " }}{PARA 0 "" 0 "" {TEXT -1 186 "(c) C
alculate the exact analytical values of the definite integrals in (a),
and use these values to calculate the absolute and relative errors in
the approximate values obtained in (a). " }}{PARA 0 "" 0 "" {TEXT -1
193 "(d) Why is the relative error for the trapezoidal rule approximat
ion for the second integral in (a) worse than the relative error for t
he trapezoidal rule approximation for the first integral? " }}{PARA 0
"" 0 "" {TEXT -1 41 "_________________________________________" }}
{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0
0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 ">
" 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }
}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT
-1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "
" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA
0 "" 0 "" {TEXT -1 41 "_________________________________________" }}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}{EXCHG {PARA 0 "> " 0
"" {MPLTEXT 1 0 1 ";" }}}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{SECT 1 {PARA 0 "" 0 "" {TEXT
-1 25 "Code for drawing pictures" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT
1 0 1 ";" }}}{SECT 1 {PARA 0 "" 0 "" {TEXT -1 28 "Code for trapezoid p
ictures " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 1000 "p1 := plot(-x^2/4+x/4+4,x=-1.5..2.5,color=red,thick
ness=2):\np2 := plot([[[-1,0],[-1,3.5],[0,4]],[[0,0],[0,4],[1,4],[1,0]
],\n [[1,4],[2,3.5],[2,0]],[[-1.5,0],[3,0]]],color=black):\np3 := pl
ots[polygonplot]([[-1,0],[-1,3.5],[0,4],[1,4],[2,3.5],[2,0]],\n \+
style=patchnogrid,color=COLOR(RGB,.8,.8,1)):\np4 := plot([[[-1,3.5
],[0,4],[1,4],[2,3.5]]$3],style=point,\n symbol=[circle,d
iamond,cross],color=black):\nt1 := plots[textplot]([[2.5,-0.1,`x`],\n \+
[-1.2,3.7,`(x ,y )`],[-0.25,4.25,`(x ,y )`],\n [1.2,4.25,`(x ,y
)`],[2.2,3.8,`(x ,y )`],\n [-1,-0.13,`x`],[0,-0.13,`x`],\n [1,-0
.13,`x`],[2,-0.13,`x`]],font=[HELVETICA,10]):\nt2 := plots[textplot]([
[-1.16,3.63,`0 0`],[-0.22,4.18,`1 1`],\n [1.23,4.18,`2 2`],[
2.23,3.73,`3 3`],\n [-.93,-0.2,`0`],[0.07,-0.2,`1`],\n [1.07,-0.2
,`2`],[2.07,-0.2,`3`]],font=[HELVETICA,8]):\nt3 := plots[textplot]([2.
5,2.9,`y = f(x)`],color=red,font=[HELVETICA,10]):\nplots[display]([p1,
p2,p3,p4,t1,t2,t3],view=[-1.5..2.5,-.2..4.6],axes=none);" }}}{PARA 0 "
" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1108 "p1 \+
:= plot(-x^2/4+x/4+4,x=-1.5..0.5,color=COLOR(RGB,1,.5,.5),thickness=1)
:\np2 := plot([[[-1,0],[-1,3.5],[0,4],[0,0]],[[-1.5,0],[.5,0]]],color=
black):\np3 := plot([[-1,3.5],[-1,3.75],[0,3.75]],color=blue):\np4 := \+
plots[polygonplot]([[-1,0],[-1,3.5],[-.5,3.75],[0,3.75],[0,0]],\n \+
style=patchnogrid,color=COLOR(RGB,.9,.9,1)):\np5 := plots[polygo
nplot]([[-1,3.5],[-1,3.75],[0,3.75],[0,4]],\n style=patchnog
rid,color=COLOR(RGB,.7,.7,1)):\np6 := plot([[[-1,3.5],[0,4]]$3],style=
point,\n symbol=[circle,diamond,cross],color=black):\np7 \+
:= plottools[arrow]([-.4,2.2],[-.4,3.75],0,.06,.06,arrow):\np8 := plot
tools[arrow]([-.4,1.55],[-.4,0],0,.06,.06,arrow):\nt1 := plots[textplo
t]([[.5,-0.1,`x`],\n [-1.25,3.7,`(x ,y )`],[-0.05,4.25,`(x ,y )`]
,\n [-1,-0.13,`x`],[0,-0.13,`x`],[-.4,2.05,`y + y`],\n [-.38,1.98,`
_____`],[-.38,1.75,`2`]],font=[HELVETICA,10]):\nt2 := plots[textplot](
[[-1.21,3.63,`0 0`],[-0.02,4.18,`1 1`],\n [-.93,-0.2,`0`],[0.07
,-0.2,`1`],[-.35,1.98,`0 1`]],font=[HELVETICA,8]):\nplots[displa
y]([p1,p2,p3,p4,p5,p6,p7,p8,t1,t2],view=[-1.5..0.5,-.2..4.5],axes=none
);" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 ""
{MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 0 "" 0 "" {TEXT -1 34 "Code for t
rapezoidal error picture" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG
{PARA 0 "> " 0 "" {MPLTEXT 1 0 1119 "p1 := plot([[0,0],[8,0]],thicknes
s=2,color=navy):\np2 := plot([[[0,0],[0,.5]],[[6,0],[6,.5]],[[8,0],[8,
.5]]],\n style=line,color=navy,thickness=2):\np
3 := plot([[[0,0],[0,-1]],[[6,0],[6,-.5]],[[8,0],[8,-1]]],color=black,
linestyle=2):\np4 := plottools[arrow]([2.75,-.3],[0,-.3],0,.13,.04,arr
ow,color=brown,linestyle=3):\np5 := plottools[arrow]([3.25,-.3],[6,-.3
],0,.13,.04,arrow,color=brown,linestyle=3):\np6 := plottools[arrow]([6
.8,-.3],[6,-.3],0,.13,.12,arrow,color=brown,linestyle=3):\np7 := plott
ools[arrow]([7.2,-.3],[8,-.3],0,.13,.12,arrow,color=brown,linestyle=3)
:\np8 := plottools[arrow]([3.8,-.8],[0,-.8],0,.13,.03,arrow,color=brow
n,linestyle=3):\np9 := plottools[arrow]([4.2,-.8],[8,-.8],0,.13,.03,ar
row,color=brown,linestyle=3):\nt1 := plots[textplot]([[0,.8,`I`],[6,.8
,`I`],[8,.8,`I`]],font=[TIMES,ROMAN,12]):\nt2 := plots[textplot]([[3,-
.3,`3 e`],[7,-.3,`e`],[4,-.76,`e`]],font=[HELVETICA,10]):\nt3 := plots
[textplot]([[4.1,-.9,`1`],[.08,.7,`1`],[6.08,.7,`2`],\n \+
[3.18,-.4,`2`],[7.1,-.4,`2`]],font=[HELVETICA,8]):\nplots[display]([
p||(1..9),t||(1..3)],axes=none,view=[0..8,-1..1]);" }}}{PARA 0 "" 0 "
" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}}{MARK "6 0 0" 0 }
{VIEWOPTS 1 1 0 1 1 1803 1 1 1 1 }{PAGENUMBERS 0 1 2 33 1 1 }