{VERSION 6 0 "IBM INTEL NT" "6.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 2 1 2 0 0 0 1 }{CSTYLE "Hyperlink" -1 17 "" 0 1 0 128 128 1 0 0 1 2 2 2 0 0 0 1 }{CSTYLE "2D Comment" -1 18 "Times" 0 1 0 0 0 0 0 0 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle1" -1 250 "Times" 1 12 167 17 223 1 1 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle2" -1 251 "Times" 1 18 0 0 0 1 2 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle3" -1 252 "Courier" 1 12 255 0 0 1 2 1 2 2 1 2 0 0 0 1 }{CSTYLE "_cstyle4" -1 253 "Times" 1 14 0 0 0 1 2 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle5" -1 254 "Times" 1 14 0 0 0 1 2 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle6" -1 255 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle7" -1 256 "Times" 1 12 0 128 128 1 2 2 1 2 2 2 0 0 0 1 }{CSTYLE "_cstyle8" -1 257 "Times" 1 12 0 0 0 1 2 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle9" -1 258 "Times" 1 12 0 0 0 1 1 2 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle10" -1 259 "Times" 1 12 0 0 0 1 2 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle11" -1 260 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle12" -1 261 "Times" 1 12 0 0 0 1 2 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle13" -1 262 "Times" 1 12 0 0 0 1 1 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle14" -1 263 "Times" 1 12 0 0 0 1 2 2 1 2 2 2 0 0 0 1 }{CSTYLE "_cstyle15" -1 264 "Times" 1 12 0 0 0 1 1 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle16" -1 265 "Times" 1 14 0 0 0 1 2 2 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle17" -1 266 "Times" 1 12 0 0 0 1 2 1 2 2 2 2 0 0 0 1 }{CSTYLE "_cstyle18" -1 267 "Times" 1 12 0 255 0 1 2 1 2 2 2 2 0 0 0 1 }{CSTYLE "" 255 269 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{PSTYLE "N ormal" -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 2 0 2 0 2 2 0 1 }{PSTYLE "_pstyle1" -1 209 1 {CSTYLE " " -1 -1 "Times" 1 12 0 0 0 1 1 1 2 2 2 2 1 1 1 1 }1 1 0 0 0 0 2 0 2 0 2 2 0 1 }{PSTYLE "_pstyle2" -1 210 1 {CSTYLE "" -1 -1 "Times" 1 18 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }1 1 0 0 0 0 2 0 2 0 2 2 0 1 }{PSTYLE "_psty le3" -1 211 1 {CSTYLE "" -1 -1 "Times" 1 18 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }1 1 0 0 0 0 2 0 2 0 2 2 0 1 }{PSTYLE "_pstyle4" -1 212 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 2 0 2 0 2 2 0 1 }{PSTYLE "_pstyle5" -1 213 1 {CSTYLE "" -1 -1 "Times" 1 18 0 0 0 1 2 1 2 2 2 2 1 1 1 1 }1 1 0 0 8 4 2 0 2 0 2 2 0 1 }{PSTYLE "_psty le6" -1 214 1 {CSTYLE "" -1 -1 "Times" 1 14 0 0 0 1 2 1 2 2 2 2 1 1 1 1 }1 1 0 0 8 2 2 0 2 0 2 2 0 1 }{PSTYLE "_pstyle7" -1 215 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 2 0 2 0 2 2 0 1 }{PSTYLE "_pstyle12" -1 220 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 }} {SECT 0 {PARA 209 "" 0 "" {TEXT 250 38 " Worksheet 3, Math 152 Spr ing 2006" }}{PARA 210 "" 0 "" {TEXT -1 0 "" }}{PARA 211 "" 0 "" {TEXT 251 22 "Integration with Maple" }}{PARA 212 "" 0 "" {TEXT -1 0 "" }} {EXCHG {PARA 212 "> " 0 "" {MPLTEXT 1 252 8 "restart;" }}}{SECT 1 {PARA 213 "" 0 "" {TEXT 253 37 "Introduction to Integration Technique " }}{SECT 1 {PARA 214 "" 0 "" {TEXT 254 32 "Discovering Integration Fo rmulas" }}{PARA 212 "" 0 "" {TEXT 255 142 "One of the ways we can make use of Maple's integration capabilities is to use them to discover (e xperimentally) certain integration formulas. " }}{EXCHG {PARA 212 "" 0 "" {TEXT 255 110 "Let's start with an integral whose value we know ( we obtained the answer in class using integration by parts):" }}{PARA 212 "" 0 "" {TEXT 255 51 " \+ " }{XPPEDIT 18 0 "int(ln(x),x) = x ln(x) -x + C" "6#/-%$intG6$- %#lnG6#%\"xGF*,(*&F*\"\"\"-F(6#F*F-F-F*!\"\"%\"CGF-" }{TEXT 255 2 " \+ " }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 13 "int(ln(x),x);" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 71 "Note that Maple does not bother to giv e us the constant of integration." }}{PARA 212 "" 0 "" {TEXT 255 14 "N ow let's try " }{XPPEDIT 18 0 "int(x ln(x),x)" "6#-%$intG6$*&%\"xG\"\" \"-%#lnG6#F'F(F'" }{TEXT 255 1 " " }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 15 "int(x*ln(x),x);" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 4 "and \+ " }{XPPEDIT 18 0 "int(x^2*ln(x),x)" "6#-%$intG6$*&%\"xG\"\"#-%#lnG6#F' \"\"\"F'" }{TEXT 255 1 " " }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 17 "in t(x^2*ln(x),x);" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 19 "and maybe o ne more " }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 17 "int(x^3*ln(x),x);" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 42 "I guess you might see a patt ern emerging. " }}{PARA 212 "" 0 "" {TEXT 255 17 "Could it be that " } {XPPEDIT 18 0 "int(x^4*ln(x),x) = x^5*ln(x)/5 -x^5/25" "6#/-%$intG6$*& %\"xG\"\"%-%#lnG6#F(\"\"\"F(,&*(F(\"\"&-F+6#F(F-F0!\"\"F-*&F(F0\"#DF3F 3" }{TEXT 255 3 " ?" }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 17 "int(x^4 *ln(x),x);" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 36 "Yes, so the gene ral formula must be " }}{PARA 212 "" 0 "" {TEXT 255 46 " \+ " }{XPPEDIT 18 0 "int(x^n*ln(x),x) = x ^(n+1)*ln(x)/(n+1) - x^(n+1)/(n+1)^2" "6#/-%$intG6$*&)%\"xG%\"nG\"\"\" -%#lnG6#F)F+F),&*()F),&F*F+F+F+F+-F-6#F)F+,&F*F+F+F+!\"\"F+*&)F),&F*F+ F+F+F+*$,&F*F+F+F+\"\"#F6F6" }{TEXT 255 1 " " }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 17 "int(x^n*ln(x),x);" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 171 "This does not exactly match our guess, but trying to te ll Maple to display the answer in exactly the form we want it, can be \+ rather involved, and is not worth our effort. " }}{PARA 212 "" 0 "" {TEXT 255 33 "One thing we can try, though, is " }{HYPERLNK 17 "simpli fy" 2 "simplify" "" }{TEXT 255 22 " with the exp option: " }}{PARA 212 "" 0 "" {TEXT 255 53 "(Note that this step may be required on Mapl e 6 only)" }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 17 "simplify(%, exp); " }}}}{SECT 1 {PARA 214 "" 0 "" {TEXT 254 27 "Using the intparts Funct ion" }}{EXCHG {PARA 212 "" 0 "" {TEXT 255 79 "We can also use Maple to see how the general formula found above evolves using " }{TEXT 257 20 "integration by parts" }{TEXT 255 2 ". " }}{PARA 212 "" 0 "" {TEXT 255 23 "To this end we use the " }{HYPERLNK 17 "intparts" 2 "intparts " "" }{TEXT 255 19 " function from the " }{HYPERLNK 17 "student" 2 "st udent" "" }{TEXT 257 1 " " }{TEXT 255 8 "package." }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 14 "with(student):" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 4 "The " }{HYPERLNK 17 "intparts" 2 "intparts" "" }{TEXT 255 29 " command takes two arguments:" }}{PARA 212 "" 0 "" {TEXT 255 48 "the first is an (inert) integral specified with " }{HYPERLNK 17 "I nt" 2 "Int" "" }{TEXT 255 4 "(); " }}{PARA 212 "" 0 "" {TEXT 255 48 "t he second argument says what we want to use as " }{XPPEDIT 18 0 "u" "6 #%\"uG" }{TEXT 255 16 " in the formula" }}{PARA 212 "" 0 "" {TEXT 255 15 " " }{XPPEDIT 18 0 "int(u,v) = u*v - int(v,u)" "6 #/-%$intG6$%\"uG%\"vG,&*&F'\"\"\"F(F+F+-F%6$F(F'!\"\"" }{TEXT 255 1 " \+ " }}{PARA 212 "" 0 "" {TEXT 255 42 "This is what needs to be done in o ur case." }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 35 "intparts(Int(x^n*ln (x), x), ln(x));" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 47 "This formu la can be cleaned up a bit using the " }{HYPERLNK 17 "applyop" 2 "appl yop" "" }{TEXT 255 69 " command, which allows us to apply a certain op eration (in this case " }{HYPERLNK 17 "simplify" 2 "simplify" "" } {TEXT 255 43 ") to only a specific part of an expression." }}{PARA 212 "" 0 "" {TEXT 255 8 "Here we " }{HYPERLNK 17 "simplify" 2 "simplif y" "" }{TEXT 255 22 " the second part (the " }{TEXT 257 1 "2" }{TEXT 255 32 ") of the previous formula (the " }{HYPERLNK 17 "%" 2 "percent " "" }{TEXT 255 4 "). " }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 22 "appl yop(simplify,2,%);" }}}{EXCHG {PARA 212 "" 0 "" {TEXT 255 56 "To obtai n the same answer we had earlier we ask for the " }{HYPERLNK 17 "value " 2 "value" "" }{TEXT 255 69 " of the integral (which you have to alwa ys do with the inert command " }{HYPERLNK 17 "Int" 2 "Int" "" }{TEXT 255 9 ") and get" }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 9 "value(%);" } }}{EXCHG {PARA 212 "" 0 "" {TEXT 255 55 "We could have used the evalua ted form of the integral, " }{HYPERLNK 17 "int" 2 "int" "" }{TEXT 255 9 "(), with " }{HYPERLNK 17 "intparts" 2 "intparts" "" }{TEXT 255 57 " also - but the pedagogical effect would not be the same:" }}{PARA 212 "> " 0 "" {MPLTEXT 1 252 35 "intparts(int(x^n*ln(x), x), ln(x));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 12 "simplify(%);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}}{SECT 1 {PARA 214 "" 0 "" {TEXT 254 28 "Partial Fractions with Maple" }}{EXCHG {PARA 212 "" 0 " " {TEXT 255 52 "A third useful tool is the partial fractions option " }{HYPERLNK 17 "parfrac" 2 "parfrac" "" }{TEXT 257 1 " " }{TEXT 255 7 " of the " }{HYPERLNK 17 "convert" 2 "convert" "" }{TEXT 257 1 " " } {TEXT 255 9 "command, " }}{PARA 212 "" 0 "" {TEXT 255 106 "e.g., on a \+ future homework you will have to find the partial fractions decomposit ion for the integrand of " }}{PARA 212 "" 0 "" {TEXT 255 44 " \+ " }{XPPEDIT 18 0 "int((2*s+2)/((s^2 +1)*(s-1)^3), s)" "6#-%$intG6$*&,&*&\"\"#\"\"\"%\"sGF*F*F)F*F**&,&*$F+ F)F*F*F*F**$,&F+F*F*!\"\"\"\"$F*F1F+" }{TEXT 255 3 " ." }}{PARA 212 " " 0 "" {TEXT 255 31 "This is how it's done in Maple:" }}{PARA 212 "> \+ " 0 "" {MPLTEXT 1 252 47 "convert((2*s+2)/((s^2+1)*(s-1)^3),'parfrac', s);" }}}}{EXCHG }}{SECT 1 {PARA 214 "" 0 "" {TEXT 254 18 "Exercise Que stions" }}{SECT 1 {PARA 214 "" 0 "" {TEXT 254 5 "Ex.1:" }}{PARA 212 " " 0 "" {TEXT 255 26 "a) Evaluate the integrals " }{XPPEDIT 18 0 "int(l n(x)/x^2,x), int(ln(x)/x^3,x), int(ln(x)/x^4,x)" "6%-%$intG6$*&-%#lnG6 #%\"xG\"\"\"*$F*\"\"#!\"\"F*-F$6$*&-F(6#F*F+*$F*\"\"$F.F*-F$6$*&-F(6#F *F+*$F*\"\"%F.F*" }{TEXT 255 2 " ." }}{PARA 212 "" 0 "" {TEXT -1 0 "" }}{PARA 212 "" 0 "" {TEXT 255 44 "b) Can you see a pattern? What do yo u think " }{XPPEDIT 18 0 "int(ln(x)/x^5,x)" "6#-%$intG6$*&-%#lnG6#%\"x G\"\"\"*$F*\"\"&!\"\"F*" }{TEXT 255 5 " is?" }}{PARA 212 "" 0 "" {TEXT 255 35 "c) What is the general formula for " }{XPPEDIT 18 0 "int (ln(x)/x^n,x), n>=2" "6$-%$intG6$*&-%#lnG6#%\"xG\"\"\")F*%\"nG!\"\"F*1 \"\"#F-" }{TEXT 255 2 " ?" }}{PARA 212 "" 0 "" {TEXT 255 82 "Write out your own formula, and compare it to Maple's answer. Are they equivale nt?" }}{PARA 212 "" 0 "" {TEXT -1 0 "" }}{PARA 212 "" 0 "" {TEXT 255 31 "d) Derive the formula with the " }{HYPERLNK 17 "intparts" 2 "intpa rts" "" }{TEXT 255 9 " command." }}{PARA 212 "" 0 "" {TEXT -1 0 "" }}} {SECT 1 {PARA 214 "" 0 "" {TEXT 254 5 "Ex.2:" }}{PARA 212 "" 0 "" {TEXT 255 60 "According to the integral table in the back of our textb ook " }}{PARA 212 "" 0 "" {TEXT 255 49 " \+ " }{XPPEDIT 18 0 "int(sqrt(x^2+1),x) = x*sqrt(x^2+1 )/2 + ln(x+sqrt(x^2+1))/2" "6#/-%$intG6$-%%sqrtG6#,&*$%\"xG\"\"#\"\"\" F.F.F,,&*(F,F.-F(6#,&*$F,F-F.F.F.F.F-!\"\"F.*&-%#lnG6#,&F,F.-F(6#,&*$F ,F-F.F.F.F.F.F-F5F." }{TEXT 255 4 " . " }}{PARA 212 "" 0 "" {TEXT 255 65 "a) What answer does Maple give you for the value of the integr al?" }}{PARA 212 "" 0 "" {TEXT -1 0 "" }}{PARA 212 "" 0 "" {TEXT 255 60 "b) Analytically show that the two formulas are equivalent. " }}} {SECT 1 {PARA 214 "" 0 "" {TEXT 254 5 "Ex.3:" }}{PARA 212 "" 0 "" {TEXT 255 72 "(a) Use Maple to find the partial fraction decomposition of the function" }}{PARA 212 "" 0 "" {XPPEDIT 18 0 "f(x) = (4*x^3-27* x^2+5*x-32)/(30*x^5-13*x^4+50*x^3-286*x^2-299*x-70);" "6#/-%\"fG6#%\"x G*&,**&\"\"%\"\"\"*$F'\"\"$F,F,*&\"#FF,*$F'\"\"#F,!\"\"*&\"\"&F,F'F,F, \"#KF3F,,.*&\"#IF,*$F'F5F,F,*&\"#8F,*$F'F+F,F3*&\"#]F,*$F'F.F,F,*&\"$' GF,*$F'F2F,F3*&\"$*HF,F'F,F3\"#qF3F3" }{TEXT 255 1 " " }}{PARA 215 "" 0 "" {TEXT -1 0 "" }}{PARA 212 "" 0 "" {TEXT 255 32 " (b) Use pa rt (a) to find " }{XPPEDIT 18 0 "int(f(x),x);" "6#-%$intG6$-%\"fG6#%\" xGF)" }{TEXT 255 2 " ." }}{PARA 212 "" 0 "" {TEXT -1 0 "" }}}{SECT 1 {PARA 214 "" 0 "" {TEXT 254 5 "Ex.4:" }}{PARA 212 "" 0 "" {TEXT 255 15 "a) Integrate " }{XPPEDIT 18 0 "int(x^2*(x^3+a)^3,x);" "6#-%$intG 6$*&%\"xG\"\"#,&*$F'\"\"$\"\"\"%\"aGF,F+F'" }{TEXT 255 31 " by hand ( use a substitution)." }}{PARA 212 "" 0 "" {TEXT 255 61 "b) Use Maple t o evaluate the integral in Part a) and get the " }{TEXT 269 12 "same r esult." }}{PARA 212 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }{TEXT 255 27 "In Maple you will need the " }{HYPERLNK 17 "change var" 2 "changevar" "" }{TEXT 255 18 " command from the " }{HYPERLNK 17 "student" 2 "student" "" }{TEXT 255 51 " package (which does integr ation by substitution). " }}{PARA 212 "" 0 "" {TEXT 255 15 "The syntax for " }{HYPERLNK 17 "changevar" 2 "changevar" "" }{TEXT 255 4 " is " }{TEXT 257 103 "changevar(expression defining the substitution, integr al in which you want to substitute, new variable)" }{TEXT 255 2 ". " } }{PARA 212 "" 0 "" {TEXT 255 29 "e.g., in order to substitute " } {XPPEDIT 18 0 "u=cos(x) " "6#/%\"uG-%$cosG6#%\"xG" }{TEXT 255 18 " in the integral " }{XPPEDIT 18 0 "int(sin(x)/(cos(x))^2, x)" "6#-%$intG6 $*&-%$sinG6#%\"xG\"\"\"*$-%$cosG6#F*\"\"#!\"\"F*" }{TEXT 255 4 " do" }}{EXCHG {PARA 212 "> " 0 "" {MPLTEXT 1 252 52 "changevar(cos(x) = u, \+ Int(sin(x)/(cos(x))^2, x), u);" }}}{PARA 212 "" 0 "" {TEXT 255 44 "Or, if you want to evaluate at the same time" }}{EXCHG {PARA 212 "> " 0 " " {MPLTEXT 1 252 52 "changevar(cos(x) = u, int(sin(x)/(cos(x))^2, x), \+ u);" }}}{PARA 212 "" 0 "" {TEXT 255 100 "After you have done the subst itution and intergration you may want to change the variable back with " }{HYPERLNK 17 "subs" 2 "subs" "" }{TEXT 257 17 "(u=x,newintegral)" }{TEXT 255 27 " and show the final result." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 123 "If it is not easy to tell whet her or not the results from part(a) and part(b) are identical, you can use Maple to check it." }}{PARA 0 "" 0 "" {TEXT -1 91 "For example, g iven a=(x+2)^5, b=x^5+10*x^4+40*x^3+80*x^2+80*x+32, you can do the fol lowing:" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 11 "a:=(x+2)^5;" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 36 "b:=x^5+10*x^4+40*x^3+80*x^2+ 80*x+32;" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "'a-b'=simplify(a-b);" }}}}}{EXCHG }{PARA 220 "" 0 "" {TEXT -1 0 "" }}}{MARK "5 0 0" 37 }{VIEWOPTS 1 1 0 1 1 1803 1 1 1 1 } {PAGENUMBERS 0 1 2 33 1 1 }