{VERSION 6 0 "IBM INTEL NT" "6.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 1 }{CSTYLE "2D Math" -1 2 "Times" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 1 }{CSTYLE "2D Comment" 2 18 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 } {CSTYLE "2D Output" 2 20 "" 0 1 0 0 255 1 0 0 0 0 0 0 0 0 0 1 } {CSTYLE "Blue Emphasis" -1 256 "Times" 0 0 0 0 255 1 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "Green Emphasis" -1 257 "Times" 1 12 0 128 0 1 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "Maroon Emphasis" -1 258 "Times" 1 12 128 0 128 1 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 259 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 260 "" 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 1 }{CSTYLE "Pu rple Emphasis" -1 261 "Times" 1 12 102 0 230 1 0 1 0 0 0 0 0 0 0 0 } {CSTYLE "Red Emphasis" -1 262 "Times" 1 12 255 0 0 1 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "Dark Red Emphasis" -1 263 "Times" 1 12 128 0 0 1 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 264 "" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 0 } {CSTYLE "" -1 265 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 266 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 267 "" 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 0 }{CSTYLE "" -1 268 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 269 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 270 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 271 "" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 0 }{CSTYLE "" -1 272 "" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 0 }{CSTYLE "" -1 273 "" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 0 }{PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }1 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Heading 1 " -1 3 1 {CSTYLE "" -1 -1 "Times" 1 18 0 0 128 1 2 1 2 2 2 2 1 1 1 1 } 1 1 0 0 8 4 3 0 3 0 2 2 0 1 }{PSTYLE "Heading 2" -1 4 1 {CSTYLE "" -1 -1 "Times" 1 14 128 0 0 1 2 1 2 2 2 2 1 1 1 1 }1 1 0 0 8 2 1 0 1 0 2 2 0 1 }{PSTYLE "Maple Output" -1 11 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }3 3 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Maple Plot" -1 13 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }3 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Normal" -1 256 1 {CSTYLE " " -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }3 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Normal" -1 257 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 1 2 2 2 1 1 1 1 }1 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Normal " -1 258 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 } 1 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "" 0 259 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 }3 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }} {SECT 0 {PARA 3 "" 0 "" {TEXT -1 19 "The harmonic series" }}{PARA 0 " " 0 "" {TEXT -1 37 "by Peter Stone, Nanaimo, B.C., Canada" }}{PARA 0 " " 0 "" {TEXT -1 19 "Version: 26.3.2007" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 8 "restart;" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 20 "The harmonic series " }{XPPEDIT 18 0 "Sum(1/n,n = 1 .. infinity )" "6#-%$SumG6$*&\"\"\"F'%\"nG!\"\"/F(;F'%)infinityG" }{TEXT -1 1 " " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 11 "The ser ies " }{XPPEDIT 18 0 "Sum(1/n,n = 1 .. infinity) = 1+1/2+1/3+1/4+1/5+1 /6+1/7+` . . . `;" "6#/-%$SumG6$*&\"\"\"F(%\"nG!\"\"/F);F(%)infinityG, 2F(F(*&F(F(\"\"#F*F(*&F(F(\"\"$F*F(*&F(F(\"\"%F*F(*&F(F(\"\"&F*F(*&F(F (\"\"'F*F(*&F(F(\"\"(F*F(%(~.~.~.~GF(" }{TEXT -1 15 " is called the " }{TEXT 261 15 "harmonic series" }{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 14 "The procedure " }{TEXT 0 7 "leftbox" }{TEXT -1 8 " in the " }{MPLTEXT 1 0 7 "student" }{TEXT -1 49 " package is useful for investigating this series." }}{PARA 0 " " 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 226 "p1 : = student[leftbox](1/x,x=1..7,6,color=red,shading=COLOR(RGB,.95,.7,.9) ,\n view=[0..7,0..2]):\np2 := plot(1/x,x=0.5..1,color=red,thicknes s=2):\nplots[display]([p1,p2],view=[0..7,0..2]);\nSum(1/i,i=1..6);\nva lue(%);\nevalf(%);" }}{PARA 13 "" 1 "" {GLPLOT2D 522 307 307 {PLOTDATA 2 "6,-%)POLYGONSG6$7&7$$\"\"\"\"\"!$F*F*7$F(F(7$$\"\"#F*F(7$ F.F+-%&COLORG6&%$RGBG$\"#&*!\"#$\"\"(!\"\"$\"\"*F:-F$6$7&F07$F.$\"++++ +]!#57$$\"\"$F*FA7$FEF+F1-F$6$7&FG7$FE$\"+LLLLLFC7$$\"\"%F*FL7$FOF+F1- F$6$7&FQ7$FO$\"+++++DFC7$$\"\"&F*FV7$FYF+F1-F$6$7&Fen7$FY$\"+++++?FC7$ $\"\"'F*Fjn7$F]oF+F1-F$6$7&F_o7$F]o$\"+nmmm;FC7$$F9F*Fdo7$FgoF+F1-%'CU RVESG6&7UF,7$$\"31++]i9Rl5!#<$\"3ygi=k7A'Q*!#=7$$\"36+++DHyI6F`p$\"3H0 @@;.VV))Fcp7$$\"39+](oozw=\"F`p$\"3/%yl0fy(>%)Fcp7$$\"3&****\\([kdW7F` p$\"34!fD'))>'[.)Fcp7$$\"3))****\\n\"\\DP\"F`p$\"3kc'y1]8dG(Fcp7$$\"3; ++]s,P,:F`p$\"3;I.ioDegmFcp7$$\"33++v8*y&H;F`p$\"3q2Au7YbOhFcp7$$\"3') ***\\(G[W[dFcp7$$\"31++v)fB:(=F`p$\"368'e:8SKM&Fcp7$$ \"3-++vQ=\"))*>F`p$\"3i++vj=pD@F`p$\"3o\\]g'p]Vq%F cp7$$\"3')*****\\c.iD#F`p$\"3'4mj==CAV%Fcp7$$\"3C++]U$e6P#F`p$\"3R&4Y \\/[t@%Fcp7$$\"3))*****\\>q0]#F`p$\"3-\\3.'*y3**RFcp7$$\"3=+++DM^IEF`p $\"3\")o\\`P#R:!QFcp7$$\"3))*****\\!ytbFF`p$\"3-ebp`AzGOFcp7$$\"3?++vQ NXpGF`p$\"3%H\"fb9T)\\[$Fcp7$$\"3.+++XDn/IF`p$\"3$[\\o-p\\\"GLFcp7$$\" 3.+++!y?#>JF`p$\"3i]u'e))Gf?$Fcp7$$\"3'****\\(3wY_KF`p$\"3M&[N^Q[)[*p'HFcp7$$\"37++v3\">)*\\$F`p$\"3w_; 5J0HdGFcp7$$\"3:++DEP/BOF`p$\"3#e(G\\:-6gFFcp7$$\"3=++](o:;v$F`p$\"3[t !Q\"G#=bm#Fcp7$$\"3=++v$)[opQF`p$\"3?Lr\"ou*=%e#Fcp7$$\"3%*****\\i%Qq* RF`p$\"3C[aPKB&=]#Fcp7$$\"3&****\\(QIKHTF`p$\"3o/SAbWq@CFcp7$$\"3#**** \\7:xWC%F`p$\"3C;7a(y-gN#Fcp7$$\"37++]Zn%)oVF`p$\"3K@p*RdL*)G#Fcp7$$\" 3C+++5FL(\\%F`p$\"3j')em$=SNA#Fcp7$$\"3#)****\\d6.BYF`p$\"3c(pJs(H3j@F cp7$$\"3(****\\(o3lWZF`p$\"3)ojTojOw5#Fcp7$$\"3O++]A))oz[F`p$\"3An2*R+ 6$\\?Fcp7$$\"3e******Hk-,]F`p$\"3%[QnA^*e**>Fcp7$$\"36+++D-eI^F`p$\"3_ ,&HvG(4\\>Fcp7$$\"3u***\\(=_(zC&F`p$\"3f!R/F!o\\0>Fcp7$$\"3M+++b*=jP&F `p$\"3qS)oVp3+'=Fcp7$$\"3g***\\(3/3(\\&F`p$\"31NN#\\[Z\">=Fcp7$$\"33++ vB4JBcF`p$\"3!H9J'pw7'F`p$\"3Xe#*\\O_&>j\"Fcp7$$\"3O++v)Q?QD'F`p$\"3#z:Tz dA!*f\"Fcp7$$\"3G+++5jypjF`p$\"39-4Xx8\"*p:Fcp7$$\"3<++]Ujp-lF`p$\"3q) *>^:O#y`\"Fcp7$$\"3++++gEd@mF`p$\"3S2CZ[_@5:Fcp7$$\"39++v3'>$[nF`p$\"3 mh$pMQ]=[\"Fcp7$$\"37++D6EjpoF`p$\"3Odkc@>ob9Fcp7$Fgo$\"3\\G9dG9dG9Fcp -%'COLOURG6&F4$\"*++++\"!\")F+F+-%&STYLEG6#%%LINEG-%*THICKNESSG6#F/-Fj o6%7S7$$\"3++++++++]FcpF.7$$\"30LL$3x&)*3^Fcp$\"357`,`cLd>F`p7$$\"3\"o m\"H2P\"Q?&Fcp$\"3?w7+ivm@>F`p7$$\"3hLLeRwX5`Fcp$\"33a]Pzo2$)=F`p7$$\" 3YLL3x%3yT&Fcp$\"3))>+vmZwX=F`p7$$\"35n;z%4\\Y_&Fcp$\"3X2-u7(p+\"=F`p7 $$\"3eL$eR-/Pi&Fcp$\"33fefku=yVB$eFcp$\"3cw#\\>uwXr\"F`p7$$\"3:+]7`l2QfFcp$\"3W)yZ\"** p/%o\"F`p7$$\"3Gnm;/j$o/'Fcp$\"3YeL$HNdPl\"F`p7$$\"3zKL3_>jUhFcp$\"3[& *QJcm'zi\"F`p7$$\"3!*****\\i^Z]iFcp$\"3C@skn$y)*f\"F`p7$$\"3U****\\(=h (ejFcp$\"3'f$\\WkLjs:F`p7$$\"3E++]P[6jkFcp$\"3uS[+y:CZ:F`p7$$\"3wK$e*[ z(yb'Fcp$\"3M$3$R=N)[_\"F`p7$$\"3Kmm;a/cqmFcp$\"3%p;<#4W7*\\\"F`p7$$\" 3%fmmmJ;R\"F`p7$$\"3Ymm\"H28IH(Fcp$\"3cN R*QQv6P\"F`p7$$\"3?n;zpSS\"R(Fcp$\"3S%R6J#H#HN\"F`p7$$\"3GLL3_?`(\\(Fc p$\"38()30CAxL8F`p7$$\"3#HLe*)>pxg(Fcp$\"3Q(Q'QkdW98F`p7$$\"3>**\\Pf4t .xFcp$\"3gyC]IB2)H\"F`p7$$\"32LLe*Gst!yFcp$\"3k#o\\enS3G\"F`p7$$\"3#)* ****\\#RW9zFcp$\"3#z%z&yk7NE\"F`p7$$\"3[***\\7j#>>!)Fcp$\"3!G)GiG$3qC \"F`p7$$\"3h**\\i!RU07)Fcp$\"3Z<#Hp$[WJ7F`p7$$\"3b***\\(=S2L#)Fcp$\"3r o\\(Q:8Y@\"F`p7$$\"3Kmmm\"p)=M$)Fcp$\"3709/To()*>\"F`p7$$\"3N****\\(=] @W)Fcp$\"39JF#*\\B`%=\"F`p7$$\"35L$e*[$z*R&)Fcp$\"37IM#*=I'4<\"F`p7$$ \"3#*****\\iC$pk)Fcp$\"332s([[zk:\"F`p7$$\"3el;H2qcZ()Fcp$\"3aI:))4]$>m6\"F`p7$$\"3y**\\ilAFj!*Fcp$\"3g-(eHDaL5\"F`p7$$\"3!HLLL)*pp;*Fc p$\"3'>R8\\*H(34\"F`p7$$\"3kKL3xe,t#*Fcp$\"374l\\3yRy5F`p7$$\"3em;HdO= y$*Fcp$\"3+'f#=gXIm5F`p7$$\"3))*****\\#>#[Z*Fcp$\"3eB8\"p!)Ga0\"F`p7$$ \"31mmT&G!e&e*Fcp$\"3QgJafOBV5F`p7$$\"3gKLL$)Qk%o*Fcp$\"3))Rmp*[iD.\"F `p7$$\"37+]iSjE!z*Fcp$\"3\"[]l9nA9-\"F`p7$$\"35+]P40O\"*)*Fcp$\"3rQlvq K)4,\"F`pF,Fg_lFa`l-%+AXESLABELSG6%Q\"x6\"Q!Fi_m-%%FONTG6#%(DEFAULTG-% %VIEWG6$;F+Fgo;F+F." 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" }}}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$SumG6$*& \"\"\"F'%\"iG!\"\"/F(;F'\"\"'" }}{PARA 11 "" 1 "" {XPPMATH 20 "6##\"# \\\"#?" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"++++]C!\"*" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 46 "The picture illlustrates the 6 th parti al sum " }{XPPEDIT 18 0 "S[6] = Sum(1/i,i = 1 .. 6);" "6#/&%\"SG6#\"\" '-%$SumG6$*&\"\"\"F,%\"iG!\"\"/F-;F,F'" }{TEXT -1 53 " as the sum of \+ the areas of the 6 shaded rectangles." }}{PARA 0 "" 0 "" {TEXT -1 0 " " }}{PARA 0 "" 0 "" {TEXT -1 46 "The six rectangles corresponding to t he terms " }{XPPEDIT 18 0 "1+1/2+1/3+1/4+1/5+1/6;" "6#,.\"\"\"F$*&F$F$ \"\"#!\"\"F$*&F$F$\"\"$F'F$*&F$F$\"\"%F'F$*&F$F$\"\"&F'F$*&F$F$\"\"'F' F$" }{TEXT -1 43 " fit over the region bounded by the graph " } {XPPEDIT 18 0 "y = 1/x;" "6#/%\"yG*&\"\"\"F&%\"xG!\"\"" }{TEXT -1 6 ", the " }{TEXT 265 1 "x" }{TEXT -1 29 " axis and the vertical lines " } {XPPEDIT 18 0 "x =1" "6#/%\"xG\"\"\"" }{TEXT -1 5 " and " }{XPPEDIT 18 0 "x = 7" "6#/%\"xG\"\"(" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 4 "Thus" }}{PARA 256 "" 0 "" {TEXT -1 2 " " }{XPPEDIT 18 0 "Int(1/ x,x = 1 .. 7) < Sum(1/i,i = 1 .. 6);" "6#2-%$IntG6$*&\"\"\"F(%\"xG!\" \"/F);F(\"\"(-%$SumG6$*&F(F(%\"iGF*/F2;F(\"\"'" }{TEXT -1 2 " " }} {PARA 258 "" 0 "" {TEXT -1 6 "Since " }}{PARA 256 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "Int(1/x,x = 1 .. 7) = ln(x);" "6#/-%$IntG6$*&\"\"\" F(%\"xG!\"\"/F);F(\"\"(-%#lnG6#F)" }{TEXT -1 1 " " }{XPPEDIT 18 0 "PIE CEWISE([7, ``],[1, ``]);" "6#-%*PIECEWISEG6$7$\"\"(%!G7$\"\"\"F(" } {XPPEDIT 18 0 "`` = ln(7)-ln(1);" "6#/%!G,&-%#lnG6#\"\"(\"\"\"-F'6#F*! \"\"" }{XPPEDIT 18 0 "``= ln(7)" "6#/%!G-%#lnG6#\"\"(" }{TEXT -1 2 ", \+ " }}{PARA 258 "" 0 "" {TEXT -1 17 "it follows that " }}{PARA 256 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "ln(7) < Sum(1/i,i = 1 .. 6);" "6#2 -%#lnG6#\"\"(-%$SumG6$*&\"\"\"F,%\"iG!\"\"/F-;F,\"\"'" }{TEXT -1 2 ". \+ " }}{PARA 0 "" 0 "" {TEXT 261 4 "Note" }{TEXT -1 2 ": " }{XPPEDIT 18 0 "Sum(1/i,i = 1 .. 6)=49/20" "6#/-%$SumG6$*&\"\"\"F(%\"iG!\"\"/F);F( \"\"'*&\"#\\F(\"#?F*" }{XPPEDIT 18 0 "``=2.45" "6#/%!G-%&FloatG6$\"$X# !\"#" }{TEXT -1 14 ", while ln(7) " }{TEXT 267 1 "~" }{TEXT -1 14 " 1. 945910149. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 83 "Sum(1/i,i=1..6)=sum(1/i,i=1..6);\n``=evalf(rhs(%)); \n'ln(7)'=evalf(evalf(ln(7),14));\n" }}{PARA 11 "" 1 "" {XPPMATH 20 "6 #/-%$SumG6$*&\"\"\"F(%\"iG!\"\"/F);F(\"\"'#\"#\\\"#?" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#/%!G$\"++++]C!\"*" }}{PARA 11 "" 1 "" {XPPMATH 20 "6 #/-%#lnG6#\"\"($\"+\\,\"f%>!\"*" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 30 "If we take a partial sum with " }{TEXT 259 1 "n" }{TEXT -1 34 " te rms, we obtain the inequality: " }}{PARA 256 "" 0 "" {TEXT -1 1 " " } {XPPEDIT 18 0 "Int(1/x,x = 1 .. n+1) < Sum(1/i,i = 1 .. n);" "6#2-%$In tG6$*&\"\"\"F(%\"xG!\"\"/F);F(,&%\"nGF(F(F(-%$SumG6$*&F(F(%\"iGF*/F3;F (F." }{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 4 "Thus" }}{PARA 256 "" 0 "" {XPPEDIT 18 0 "ln(n+1) < Sum(1/i,i = 1 .. n);" "6#2-%#lnG6#,&% \"nG\"\"\"F)F)-%$SumG6$*&F)F)%\"iG!\"\"/F.;F)F(" }{TEXT -1 1 "." }} {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 6 "Since " } {XPPEDIT 18 0 "ln(N+1)" "6#-%#lnG6#,&%\"NG\"\"\"F(F(" }{TEXT -1 10 " t ends to " }{XPPEDIT 18 0 "infinity" "6#%)infinityG" }{TEXT -1 4 " as \+ " }{XPPEDIT 18 0 "N -> infinity" "6#f*6#%\"NG7\"6$%)operatorG%&arrowG6 \"%)infinityGF*F*F*" }{TEXT -1 25 ", we see that the series " } {XPPEDIT 18 0 "Sum(1/i,i = 1 .. infinity);" "6#-%$SumG6$*&\"\"\"F'%\"i G!\"\"/F(;F'%)infinityG" }{TEXT -1 23 " diverges to infinity." }} {PARA 0 "" 0 "" {TEXT -1 65 "Notice that the individual terms of the h armonic series given by " }{XPPEDIT 18 0 "a[n]=1/n" "6#/&%\"aG6#%\"nG* &\"\"\"F)F'!\"\"" }{TEXT -1 65 ", clearly tend to 0, so we have an exa mple of a series for which " }{XPPEDIT 18 0 "Limit(a[n],n=infinity)=0 " "6#/-%&LimitG6$&%\"aG6#%\"nG/F*%)infinityG\"\"!" }{TEXT -1 6 ", but \+ " }{XPPEDIT 18 0 "Sum(a[n],n=1..infinity)=infinity" "6#/-%$SumG6$&%\"a G6#%\"nG/F*;\"\"\"%)infinityGF." }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 42 "Computations involving the harmonic ser ies" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 14 "The procedure " }{MPLTEXT 1 0 3 "add" }{TEXT -1 49 " in t he following code computes the partial sum " }{XPPEDIT 18 0 "Sum(1/i, i = 1 .. 1000000);" "6#-%$SumG6$*&\"\"\"F'%\"iG!\"\"/F(;F'\"(+++\"" } {TEXT -1 146 " of 1000000 terms of the harmonic series. Employing har dware floating point arithmetic enables the calculation to be complete d in a few seconds. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 37 "evalf(evalhf(add(1/i,i=1..1000000)));" }} {PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+sEFR9!\")" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 14 "The procedure " } {MPLTEXT 1 0 3 "sum" }{TEXT -1 36 " gives the result much more rapidly ." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 49 "i := 'i':\nevalf(evalf(sum(1/i,i=1..1000000),14));" } }{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+sEFR9!\")" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 14 "The procedure " } {MPLTEXT 1 0 3 "sum" }{TEXT -1 75 " actually computes the finite sum b y using a special mathematical function " }{XPPEDIT 18 0 "Psi" "6#%$Ps iG" }{TEXT -1 31 " and the mathematical constant " }{XPPEDIT 18 0 "gam ma" "6#%&gammaG" }{TEXT -1 32 ", which we shall discuss later. " }} {PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 32 "Sum(1/i,i=1..n)=sum(1/i,i=1..n);" }}{PARA 11 "" 1 "" {XPPMATH 20 " 6#/-%$SumG6$*&\"\"\"F(%\"iG!\"\"/F);F(%\"nG,&-%$PsiG6#,&F-F(F(F(F(%&ga mmaGF(" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 77 "The following comput ations show that the partial sums of the harmonic series " }{XPPEDIT 18 0 "Sum(1/n,n=1..infinity)" "6#-%$SumG6$*&\"\"\"F'%\"nG!\"\"/F(;F'%) infinityG" }{TEXT -1 19 " grow very slowly." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 217 "H := n -> [Sum(1/ i,i=1..n),`=`,evalf(sum(1./i,i=1..n))]:\nmatrix([H(1),H(2),H(3),[`:`,` :`,`:`],H(100),[`:`,`:`,`:`],\nH(10^4),[`:`,`:`,`:`],H(10^6),[`:`,`:`, `:`],H(10^8),[`:`,`:`,`:`],\nH(10^16),[`:`,`:`,`:`],H(10^32)]);" }} {PARA 11 "" 1 "" {XPPMATH 20 "6#-%'matrixG6#717%-%$SumG6$*&\"\"\"F,%\" iG!\"\"/F-;F,F,%\"=G$F,\"\"!7%-F)6$F+/F-;F,\"\"#F1$\"+++++:!\"*7%-F)6$ F+/F-;F,\"\"$F1$\"+LLLL=F<7%%\":GFFFF7%-F)6$F+/F-;F,\"$+\"F1$\"+=vP(=& F " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 41 "In the previous section we showed that " } {XPPEDIT 18 0 "ln(N+1) " 0 "" {MPLTEXT 1 0 18 "evalf(exp(100)-1);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+Ur6)o#\"#M" }}}{PARA 0 "" 0 "" {TEXT -1 30 "Le t's take the sum of around " }{XPPEDIT 18 0 "3*`.`*10^43;" "6#*(\"\"$ \"\"\"%\".GF%\"#5\"#V" }{TEXT -1 7 " terms." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 39 "Sum(1/i,i=1..3*10^ 43);\nevalf(value(%));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$SumG6$*& \"\"\"F'%\"iG!\"\"/F(;F'\"M+++++++++++++++++++++I" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+q)po+\"!\"(" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }} {PARA 0 "" 0 "" {TEXT -1 58 "In order to obtain a sum larger than 200, we could choose " }{TEXT 268 1 "N" }{TEXT -1 9 " so that " }{XPPEDIT 18 0 "200 <= ln(N+1);" "6#1\"$+#-%#lnG6#,&%\"NG\"\"\"F*F*" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 12 " This gives " }{XPPEDIT 18 0 "exp (200)-1 <= N;" "6#1,&-%$expG6#\"$+#\"\"\"F)!\"\"%\"NG" }{TEXT -1 1 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 18 "evalf(exp(200)-1);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+oP(f A(\"#x" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 261 4 "Note" }{TEXT -1 89 ": The number of electrons, protons and neutrons in the universe is estimated to be about " }{XPPEDIT 18 0 "10^79" "6# *$\"#5\"#z" }{TEXT -1 47 ", so we certainly need a large number of ter ms." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 41 "Sum(1/i,i=1..0.7226e87);\nevalf(value(%));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$SumG6$*&\"\"\"F'%\"iG!\"\"/F(;F'$\"%Es\"# $)" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+$>sd+#!\"(" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 37 "In order to obtain a s um larger than " }{XPPEDIT 18 0 "10^6" "6#*$\"#5\"\"'" }{TEXT -1 18 ", we could choose " }{TEXT 269 1 "N" }{TEXT -1 9 " so that " }{XPPEDIT 18 0 "10^6 <= ln(N+1);" "6#1*$\"#5\"\"'-%#lnG6#,&%\"NG\"\"\"F,F," } {TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 12 " This gives " }{XPPEDIT 18 0 "exp(10^6)-1 <= N;" "6#1,&-%$expG6#*$\"#5\"\"'\"\"\"F+!\"\"%\"NG " }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 19 "evalf(exp(10^6)-1);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+(R:K.$\"'&GM%" }}}{PARA 0 "" 0 "" {TEXT -1 11 " Th is is " }{XPPEDIT 18 0 ".3033215397*10^434295" "6#*&-%&FloatG6$\"+(R: K.$!#5\"\"\"*$\"#5\"'&HM%F)" }{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 44 "Sum(1/i,i=1..0.304 e434295);\nevalf(value(%));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$SumG 6$*&\"\"\"F'%\"iG!\"\"/F(;F'$\"$/$\"'#HM%" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+z0++5!\"$" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4 "" 0 " " {TEXT -1 17 "Euler's constant " }{XPPEDIT 18 0 "gamma" "6#%&gammaG" }{TEXT -1 1 " " }}{PARA 0 "" 0 "" {TEXT -1 38 "The curve in the follow ing picture is " }{XPPEDIT 18 0 "y = 1/x" "6#/%\"yG*&\"\"\"F&%\"xG!\" \"" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 " > " 0 "" {MPLTEXT 1 0 380 "rtbox := n -> [[n,0],[n+1,0],[n+1,1/(n+1)], [n,1/(n+1)]]:\nltbox := n -> [[n,1/(n+1)],[n+1,1/(n+1)],[n+1,1/n],[n,1 /n]]:\np1 := plot(1/x,x=0.5..7,thickness=2,color=red):\np2 := plots[po lygonplot]([seq(ltbox(n),n=1..6)],color=COLOR(RGB,.95,.6,.8)):\np3 := \+ plots[polygonplot]([seq(rtbox(n),n=1..6)],color=COLOR(RGB,.7,.95,.7)): \nplots[display]([p1,p2,p3],view=[0..7,0..2],tickmarks=[7,3]);" }} {PARA 13 "" 1 "" {GLPLOT2D 518 303 303 {PLOTDATA 2 "6(-%'CURVESG6%7Y7$ $\"3++++++++]!#=$\"\"#\"\"!7$$\"3EL$3_v.UN&F*$\"3#>xxDM\"pn=!#<7$$\"3] mmT5vS3dF*$\"3g2LqF*$\"36mQr(eG=U\"F37$$\"3M m;z%>y&\\wF*$\"3vm4>A;E28F37$$\"3)**\\(oaPwU$)F*$\"3e&[ZVbV')>\"F37$$ \"3hLLe9$\\f.*F*$\"3M1%\\8e!p16F37$$\"3wLLLe(HPt*F*$\"35O.`!*oH`-%)GwF*7$$\"3(**\\7`c]TW\"F3$\"3WVc#Gu& [CpF*7$$\"3?Lekeh/#e\"F3$\"3+i%fv3G4K'F*7$$\"3)**\\i!>&*\\> 4dk:eF*7$$\"3emmT&>()3'=F3$\"3u9Sdj3yt`F*7$$\"3IL$3x`@a)>F3$\"3-I9*3x8 n.&F*7$$\"3K++D6xhD@F3$\"3J54g3[^/ZF*7$$\"3!****\\Pa*QmAF3$\"3ua\\naTI 7WF*7$$\"3z***\\()G\\?S#F3$\"3'o&****3>6jTF*7$$\"3.LekL8CDDF3$\"3;JxI] v,gRF*7$$\"3ammT!fG#F*7$$\"3?**\\PCi *Hq%F3$\"3@:\"=s1/j7#F*7$$\"3@mm;*HXW$[F3$\"3c(e#fO'*[o?F*7$$\"3/++vV_ zu\\F3$\"3)\\9qB)H85?F*7$$\"3/Lek`J(>5&F3$\"3_T,k$*f-g>F*7$$\"3B++D,A, T_F3$\"3!H(3?w$G!3>F*7$$\"3[l\"z%4r$=P&F3$\"3m$4.=ag:'=F*7$$\"3;+D1Moe 3bF3$\"3[4'F3$\"3eZG0083:;F*7$$\"3;++]-& osJ'F3$\"3a>e$ejiHe\"F*7$$\"37m;/rVDhkF3$\"3uay#Q4(oZ:F*7$$\"3gKLL[q.! f'F3$\"3WL>%>:Uu^\"F*7$$\"3r*\\7GCYts'F3$\"3+@5OU-Z'[\"F*7$$\"3#**\\(= i'o(eoF3$\"3'f)RY\\w)zX\"F*7$$\"\"(F-$\"3\\G9dG9dG9F*-%'COLOURG6&%$RGB G$\"*++++\"!\")$F-F-F^]l-%*THICKNESSG6#F,-%)POLYGONSG6)7&7$$\"\"\"F-$ \"+++++]!#57$F+Fi]l7$F+Fg]l7$Fg]lFg]l7&7$F+$\"+LLLLLF[^l7$$\"\"$F-Fa^l 7$Fd^lFi]lF\\^l7&7$Fd^l$\"+++++DF[^l7$$\"\"%F-Fi^l7$F\\_lFa^lFc^l7&7$F \\_l$\"+++++?F[^l7$$\"\"&F-Fa_l7$Fd_lFi^lF[_l7&7$Fd_l$\"+nmmm;F[^l7$$ \"\"'F-Fi_l7$F\\`lFa_lFc_l7&7$F\\`l$\"+H9dG9F[^l7$Fc\\lFa`l7$Fc\\lFi_l F[`l-%&COLORG6&Fj\\l$\"#&*!\"#$F]`l!\"\"$\"\")F\\al-Fc]l6)7&7$Fg]lF^]l 7$F+F^]lF\\^lFf]l7&Fcal7$Fd^lF^]lFc^lF`^l7&Feal7$F\\_lF^]lF[_lFh^l7&Fg al7$Fd_lF^]lFc_lF`_l7&Fial7$F\\`lF^]lF[`lFh_l7&F[bl7$Fc\\lF^]lFc`lF``l -Ff`l6&Fj\\l$Fd\\lF\\alFh`lF`bl-%*AXESTICKSG6$Fd\\lFe^l-%+AXESLABELSG6 $Q\"x6\"Q!Fhbl-%%VIEWG6$;F^]lFc\\l;F^]lF+" 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" }}}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 64 "In the first section a similar \+ picture was used to suggest that " }}{PARA 256 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "Int(1/x,x = 1 .. n+1) = ``;" "6#/-%$IntG6$*&\"\"\"F(% \"xG!\"\"/F);F(,&%\"nGF(F(F(%!G" }{XPPEDIT 18 0 "ln(n+1) < Sum(1/i,i = 1 .. n);" "6#2-%#lnG6#,&%\"nG\"\"\"F)F)-%$SumG6$*&F)F)%\"iG!\"\"/F.;F )F(" }{TEXT -1 6 ", for " }{XPPEDIT 18 0 "n >=1" "6#1\"\"\"%\"nG" } {TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 58 "The infinite sum of the areas cut off from the rectangles " }{TEXT 261 15 "above the curve" } {TEXT -1 1 " " }{XPPEDIT 18 0 "y=1/x" "6#/%\"yG*&\"\"\"F&%\"xG!\"\"" } {TEXT -1 18 " turns out to be " }{TEXT 261 6 "finite" }{TEXT -1 1 ". " }}{PARA 256 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "Int(1/x,x=n..n+1) =ln(x)" "6#/-%$IntG6$*&\"\"\"F(%\"xG!\"\"/F);%\"nG,&F-F(F(F(-%#lnG6#F) " }{TEXT -1 1 " " }{XPPEDIT 18 0 "PIECEWISE([n+1,``],[n,``]) = ln(n+1) -ln(n)" "6#/-%*PIECEWISEG6$7$,&%\"nG\"\"\"F*F*%!G7$F)F+,&-%#lnG6#,&F)F *F*F*F*-F/6#F)!\"\"" }{TEXT -1 3 " = " }{XPPEDIT 18 0 "ln((n+1)/n)" "6 #-%#lnG6#*&,&%\"nG\"\"\"F)F)F)F(!\"\"" }{TEXT -1 2 ", " }}{PARA 0 "" 0 "" {TEXT -1 45 "so this total area is the sum of the series " } {XPPEDIT 18 0 "Sum(1/n-ln(n+1)+ln(n),n = 1 .. infinity) = Sum(1/n-ln(( n+1)/n),n = 1 .. infinity);" "6#/-%$SumG6$,(*&\"\"\"F)%\"nG!\"\"F)-%#l nG6#,&F*F)F)F)F+-F-6#F*F)/F*;F)%)infinityG-F%6$,&*&F)F)F*F+F)-F-6#*&,& F*F)F)F)F)F*F+F+/F*;F)F4" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 128 "We can establish the convergence \+ of this series by comparison with the series whose terms are the areas of the pink rectangles. " }}{PARA 0 "" 0 "" {TEXT -1 16 "This series \+ is: " }}{PARA 256 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "Sum(1/n-1/(n+ 1),n = 1 .. infinity) = Sum(1/(n*(n+1)),n = 1 .. infinity);" "6#/-%$Su mG6$,&*&\"\"\"F)%\"nG!\"\"F)*&F)F),&F*F)F)F)F+F+/F*;F)%)infinityG-F%6$ *&F)F)*&F*F),&F*F)F)F)F)F+/F*;F)F0" }{TEXT -1 6 " = 1. " }}{PARA 0 "" 0 "" {TEXT -1 31 "The partial sums of the series " }{XPPEDIT 18 0 "Sum (1/n-ln((n+1)/n),n = 1 .. infinity)" "6#-%$SumG6$,&*&\"\"\"F(%\"nG!\" \"F(-%#lnG6#*&,&F)F(F(F(F(F)F*F*/F);F(%)infinityG" }{TEXT -1 16 " have the form " }{XPPEDIT 18 0 "Sum(1/i,i = 1 .. n)-ln(n+1);" "6#,&-%$Sum G6$*&\"\"\"F(%\"iG!\"\"/F);F(%\"nGF(-%#lnG6#,&F-F(F(F(F*" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 46 "We tabulate some values of these pa rtial sums." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 236 "H := n->[`10`^n,evalf(sum(1/i,i=1..10^n)),evalf(ln (10^n+1)),\nevalf(evalf(sum(1/i,i=1..10^n)-ln(10^n+1),15))]:\nmatrix([ [n,Sum(1/i,i=1..n),ln(n+1),Sum(1/i,i=1..n)-ln(n+1)],\nH(0),H(1),H(2),H (3),H(4),H(5),H(6),H(7),H(8),H(9),H(10),H(100)]);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%'matrixG6#7/7&%\"nG-%$SumG6$*&\"\"\"F-%\"iG!\"\"/F.;F -F(-%#lnG6#,&F(F-F-F-,&F)F-F2F/7&F-$F-\"\"!$\"+1=ZJp!#5$\"+%>G&oIF<7&% #10G$\"+a#o*GH!\"*$\"+t_*yR#FC$\"+7)H2J&F<7&*$)F@\"\"#F-$\"+=vP(=&FC$ \"+<07:YFC$\"+3+dAdF<7&*$)F@\"\"$F-$\"+h3Z&[(FC$\"+zZv3pFC$\"+73;ndF<7 &*$)F@\"\"%F-$\"+Ogg(y*FC$\"+n.W5#*FC$\"+\"pc;x&F<7&*$)F@\"\"&F-$\"+7Y ,47!\")$\"+YNH^6Ffo$\"+\\m5sdF<7&*$)F@\"\"'F-$\"+sEFR9Ffo$\"+c6b\"Q\"F fo$\"+\\;:sdF<7&*$)F@\"\"(F-$\"+O6`p;Ffo$\"+v&4=h\"Ffo$\"+\\h:sdF<7&*$ )F@\"\")F-$\"+T'*y**=Ffo$\"+v!o?%=Ffo$\"+*fc@x&F<7&*$)F@\"\"*F-$\"+]\" [+8#Ffo$\"+%eEB2#Ffo$\"+Wm:sdF<7&*$)F@\"#5F-$\"+fmIgBFfo$\"+$4&e-BFfo$ \"+\\m:sdF<7&*$)F@\"$+\"F-$\"+]sN3B!\"($FjrFcsF[s" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 30 "The limit of this sequenc e is " }{TEXT 261 16 "Euler's constant" }{TEXT -1 2 " " }{XPPEDIT 18 0 "gamma" "6#%&gammaG" }{TEXT -1 1 " " }{TEXT 260 1 "~" }{TEXT -1 14 " 0.5772156649." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 95 "Limit(Sum(1/i,i=1..n)-ln(n+1),n=infinity);\nLimi t(sum(1/i,i=1..n)-ln(n+1),n=infinity);\nvalue(%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%&LimitG6$,&-%$SumG6$*&\"\"\"F+%\"iG!\"\"/F,;F+%\"nGF+ -%#lnG6#,&F0F+F+F+F-/F0%)infinityG" }}{PARA 11 "" 1 "" {XPPMATH 20 "6# -%&LimitG6$,(-%$PsiG6#,&%\"nG\"\"\"F,F,F,%&gammaGF,-%#lnGF)!\"\"/F+%)i nfinityG" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#%&gammaG" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 47 "Sum(1/n-l n(n+1)+ln(n),n=1..infinity);\nvalue(%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$SumG6$,(*&\"\"\"F(%\"nG!\"\"F(-%#lnG6#,&F)F(F(F(F*-F,6#F)F(/F );F(%)infinityG" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#%&gammaG" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "ev alf(gamma,20);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"5hgG`,\\m:sd!#?" }}}{PARA 0 "" 0 "" {TEXT -1 1 " " }}{PARA 0 "" 0 "" {TEXT -1 25 "In fa ct the psi function " }{XPPEDIT 18 0 "Psi" "6#%$PsiG" }{TEXT -1 57 ", \+ which appears above, is defined for a positive integer " }{TEXT 270 1 "n" }{TEXT -1 3 " by" }}{PARA 256 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "Psi(n) = Sum(1/i,i = 1 .. n-1)-gamma;" "6#/-%$PsiG6#%\"nG,&-%$SumG6 $*&\"\"\"F-%\"iG!\"\"/F.;F-,&F'F-F-F/F-%&gammaGF/" }{TEXT -1 1 "," }} {PARA 0 "" 0 "" {TEXT -1 17 "so, for example, " }{XPPEDIT 18 0 "Psi(1) =-gamma" "6#/-%$PsiG6#\"\"\",$%&gammaG!\"\"" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 17 "ev alf(Psi(1),20);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$!5hgG`,\\m:sd!#?" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 8 "Examples" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }} }{SECT 1 {PARA 4 "" 0 "" {TEXT -1 9 "Example 1" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 257 "" 0 "" {TEXT 258 8 "Question" } {TEXT 264 2 ": " }}{PARA 0 "" 0 "" {TEXT -1 21 "Show that the series \+ " }{XPPEDIT 18 0 "Sum(3/(5*n+7),n=1..infinity)" "6#-%$SumG6$*&\"\"$\" \"\",&*&\"\"&F(%\"nGF(F(\"\"(F(!\"\"/F,;F(%)infinityG" }{TEXT -1 23 " \+ diverges to infinity." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 257 " " 0 "" {TEXT 263 8 "Solution" }{TEXT 271 4 ": " }}{PARA 0 "" 0 "" {TEXT -1 5 "When " }{XPPEDIT 18 0 "7 <= n" "6#1\"\"(%\"nG" }{TEXT -1 4 ", " }{XPPEDIT 18 0 "1/(2*n)" "6#*&\"\"\"F$*&\"\"#F$%\"nGF$!\"\"" }{TEXT -1 4 " = " }{XPPEDIT 18 0 "3/(5*n+7) >= 3/(6*n)" "6#1*&\"\"$\" \"\"*&\"\"'F&%\"nGF&!\"\"*&F%F&,&*&\"\"&F&F)F&F&\"\"(F&F*" }{TEXT -1 2 " ." }}{PARA 0 "" 0 "" {TEXT -1 7 "Since " }{XPPEDIT 18 0 "Sum(1/(2 *n),n = 7 .. infinity);" "6#-%$SumG6$*&\"\"\"F'*&\"\"#F'%\"nGF'!\"\"/F *;\"\"(%)infinityG" }{TEXT -1 31 " diverges to infinity, so does " } {XPPEDIT 18 0 "Sum(3/(5*n+7),n = 7 .. infinity)" "6#-%$SumG6$*&\"\"$\" \"\",&*&\"\"&F(%\"nGF(F(\"\"(F(!\"\"/F,;F-%)infinityG" }{TEXT -1 1 ". " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 39 "Sum(3/(5*n+7),n=1..infinity);\nvalue(%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$SumG6$,$*&\"\"\"F(,&%\"nG\"\"&\"\"(F(!\"\"\"\"$/F*;F (%)infinityG" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#%)infinityG" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 9 "Example 2" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 257 "" 0 "" {TEXT 258 8 "Question " }{TEXT 272 4 ": " }}{PARA 0 "" 0 "" {TEXT -1 21 "Show that the ser ies " }{XPPEDIT 18 0 "Sum(2/((n+1)*(n+3)),n=1..infinity)" "6#-%$SumG6$ *&\"\"#\"\"\"*&,&%\"nGF(F(F(F(,&F+F(\"\"$F(F(!\"\"/F+;F(%)infinityG" } {TEXT -1 28 " converges and find its sum." }}{PARA 257 "" 0 "" {TEXT 263 8 "Solution" }{TEXT 273 4 ": " }}{PARA 0 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "2/((n+1)*(n+3))<=2/n^2" "6#1*&\"\"#\"\"\"*&,&%\"nGF&F& F&F&,&F)F&\"\"$F&F&!\"\"*&F%F&*$F)F%F," }{TEXT -1 7 " for " } {XPPEDIT 18 0 "n>=1" "6#1\"\"\"%\"nG" }{TEXT -1 4 ", so" }}{PARA 0 "" 0 "" {TEXT -1 2 " " }{XPPEDIT 18 0 "Sum(2/((n+1)*(n+3)),n = 1 .. infi nity)" "6#-%$SumG6$*&\"\"#\"\"\"*&,&%\"nGF(F(F(F(,&F+F(\"\"$F(F(!\"\"/ F+;F(%)infinityG" }{TEXT -1 30 " converges by comparison with " } {XPPEDIT 18 0 "Sum(2/n^2,n = 1 .. infinity)=2*Sum(1/n^2,n = 1 .. infin ity)" "6#/-%$SumG6$*&\"\"#\"\"\"*$%\"nGF(!\"\"/F+;F)%)infinityG*&F(F)- F%6$*&F)F)*$F+F(F,/F+;F)F/F)" }{TEXT -1 3 " = " }{XPPEDIT 18 0 "Pi^2/3 " "6#*&%#PiG\"\"#\"\"$!\"\"" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 92 "To find the sum of the series n ote that the general term has the partial fraction expansion " }} {PARA 256 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "2/((n+1)*(n+3))=1/(n+ 1)-1/(n+3)" "6#/*&\"\"#\"\"\"*&,&%\"nGF&F&F&F&,&F)F&\"\"$F&F&!\"\",&*& F&F&,&F)F&F&F&F,F&*&F&F&,&F)F&F+F&F,F," }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 35 "convert (2/((n+1)*(n+3)),parfrac,n);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#,&*&\" \"\"F%,&%\"nGF%F%F%!\"\"F%*&F%F%,&F'F%\"\"$F%F(F(" }}}{EXCHG {PARA 0 " > " 0 "" {MPLTEXT 1 0 1 ";" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 9 "We have: " }}{PARA 259 "" 0 "" {TEXT -1 1 " " } {XPPEDIT 18 0 "Sum(1/(i+1)-1/(i+3),i = 1 .. n) = ``(1/2-1/4)+``(1/3-1/ 5)+``(1/4-1/6)+` . . . `+``(1/n-1/(n+2))+``(1/(n+1)-1/(n+3))" "6#/-%$S umG6$,&*&\"\"\"F),&%\"iGF)F)F)!\"\"F)*&F)F),&F+F)\"\"$F)F,F,/F+;F)%\"n G,.-%!G6#,&*&F)F)\"\"#F,F)*&F)F)\"\"%F,F,F)-F56#,&*&F)F)F/F,F)*&F)F)\" \"&F,F,F)-F56#,&*&F)F)F;F,F)*&F)F)\"\"'F,F,F)%(~.~.~.~GF)-F56#,&*&F)F) F2F,F)*&F)F),&F2F)F9F)F,F,F)-F56#,&*&F)F),&F2F)F)F)F,F)*&F)F),&F2F)F/F )F,F,F)" }{TEXT -1 2 ". " }}{PARA 0 "" 0 "" {TEXT -1 33 "This partial \+ sum \"telescopes\" to " }{XPPEDIT 18 0 "1/2+1/3-1/(n+2)-1/(n+3) = 5/6- (2*n+5)/((n+2)*(n+3)" "6#/,**&\"\"\"F&\"\"#!\"\"F&*&F&F&\"\"$F(F&*&F&F &,&%\"nGF&F'F&F(F(*&F&F&,&F-F&F*F&F(F(,&*&\"\"&F&\"\"'F(F&*&,&*&F'F&F- F&F&F2F&F&*&,&F-F&F'F&F&,&F-F&F*F&F&F(F(" }{TEXT -1 1 "." }}{PARA 0 " " 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 38 "sum(1 /(i+1)-1/(i+3),i=1..n);\nvalue(%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6# ,&*&,&\"\"&\"\"\"%\"nG\"\"#F'*&,&F(F'\"\"$F'F',&F(F'F)F'F'!\"\"F.#F&\" \"'F'" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#,&*&,&\"\"&\"\"\"%\"nG\"\"#F' *&,&F(F'\"\"$F'F',&F(F'F)F'F'!\"\"F.#F&\"\"'F'" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 68 "The limit of the sequence of partial sums as n tends to infinity is " }{XPPEDIT 18 0 "5/6" "6#* &\"\"&\"\"\"\"\"'!\"\"" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 " " }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 45 "Sum(2/((n+1)*(n+3)),n=1. .infinity);\nvalue(%);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%$SumG6$,$* &\"\"\"F(*&,&%\"nGF(F(F(F(,&F+F(\"\"$F(F(!\"\"\"\"#/F+;F(%)infinityG" }}{PARA 11 "" 1 "" {XPPMATH 20 "6##\"\"&\"\"'" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 125 "Note that the argument u sed to find the sum of the series also establishes the convergence ind ependently of the first method." }}{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 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{MARK "4 0 0" 0 } {VIEWOPTS 1 1 0 1 1 1803 1 1 1 1 }{PAGENUMBERS 0 1 2 33 1 1 }