{VERSION 4 0 "IBM INTEL NT" "4.0" } {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 "" -1 256 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 257 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 258 "" 0 1 0 0 0 0 1 0 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 1 0 0 0 0 0 0 0 0 1 } {CSTYLE "" -1 261 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 262 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 263 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 264 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 265 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 } {CSTYLE "" -1 266 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 267 "" 0 1 0 0 0 0 0 1 0 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 "Normal" -1 256 1 {CSTYLE "" -1 -1 "Times" 1 18 0 0 0 1 2 1 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 18 0 0 0 1 2 1 2 2 2 2 1 1 1 1 }3 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Normal" -1 258 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" -1 259 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" -1 260 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 }} {SECT 0 {EXCHG {PARA 256 "" 0 "" {TEXT -1 6 "C3M12a" }}}{EXCHG {PARA 257 "" 0 "" {TEXT -1 50 "Evaluating Integrals using Cylindrical Coordi nates" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 525 "Let\222s begin with an \+ integral in rectangular coordinates, plot the solid which is the domai n of the integral, plot the same solid using cylindrical coordinates, \+ and then transform the integral into one using cylindrical coordinates . A simple first step is to include the variable of integration in th e limits of the integral, which allows one to see the appropriate equa tions that define the surfaces. Immediately below the integral we wil l list the necessary packages and the Maple command that would produce this integral." }}}{EXCHG {PARA 0 "" 0 "" {TEXT 256 10 "Example: \001 " }{XPPEDIT 18 0 "Int(Int(Int(x*z,z=0..sqrt(4-x^2-y^2)),x=0..sqrt(1-y^ 2)),y=0..1)=Int(Int(Int(x*z,z=(z=0)..(z=sqrt(4-x^2-y^2))),x=(x=0)..(x= sqrt(1-y^2))),y=(y=0)..(y=1))" "6#/-%$IntG6$-F%6$-F%6$*&%\"xG\"\"\"%\" zGF-/F.;\"\"!-%%sqrtG6#,(\"\"%F-*$F,\"\"#!\"\"*$%\"yGF8F9/F,;F1-F36#,& F-F-*$F;F8F9/F;;F1F--F%6$-F%6$-F%6$*&F,F-F.F-/F.;/F.F1/F.-F36#,(F6F-*$ F,F8F9*$F;F8F9/F,;/F,F1/F,-F36#,&F-F-*$F;F8F9/F;;/F;F1/F;F-" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 27 "with(student): with(plots): " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 64 "A:=Tripleint(x*z,z=0..s qrt(4-x^2-y^2),x=0..sqrt(1-y^2),y=0..1);\n" }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 15 "valA:=value(A);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 39 "We will use plot3d in parametric form, " }{TEXT 257 7 "[x,y,z] " }{TEXT -1 209 ", with one of the variables eliminated so that just t wo are allowed to vary and that variable does not appear. The inner in tegral varies between two surfaces which, for intuitive reasons, we wi ll designate as " }{TEXT 258 5 "floor" }{TEXT -1 6 "1 and " }{TEXT 259 4 "roof" }{TEXT -1 107 "1. Pay close attention to the similaritie s between the syntax for the triple integral and for these plots." }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 61 "floor1:=plot3d([x,y,0],x=0.. sqrt(1-y^2),y=0..1,color=green):\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 73 "roof1:=plot3d([x,y,sqrt(4-x^2-y^2)],x=0..sqrt(1-y^2), y=0..1,color=blue):\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 23 "di splay(floor1,roof1);\n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 36 "Now let \222s add the cylindrical wall, " }{TEXT 260 5 "cwall" }{TEXT -1 35 "1 , and the two flat vertical walls." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 64 "cwall1:=plot3d([sqrt(1-y^2),y,z],z=0..sqrt(3),y=0..1, color=red):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 59 "vwall1:=plot 3d([0,y,z],z=0..sqrt(4-y^2),y=0..1,color=cyan):" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 59 "vwall2:=plot3d([x,0,z],z=0..sqrt(4-x^2),x=0..1 ,color=plum):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 43 "display(fl oor1,roof1,cwall1,vwall1,vwall2);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 191 "We must see how to sketch this same solid in cylindrical coordina tes. We know at this point that the solid is a quarter of a circular \+ cylinder, cut off on the bottom by a horizontal plane ( " }{XPPEDIT 18 0 "z=0" "6#/%\"zG\"\"!" }{TEXT -1 32 " ) and on the top by a sphere ( " }{XPPEDIT 18 0 "x^2+y^2+z^2=4" "6#/,(*$%\"xG\"\"#\"\"\"*$%\"yGF'F (*$%\"zGF'F(\"\"%" }{TEXT -1 65 " ). All of this takes place in the f irst octant which is where " }{XPPEDIT 18 0 "x>=0" "6#1\"\"!%\"xG" } {TEXT -1 8 " and " }{XPPEDIT 18 0 "y>=0" "6#1\"\"!%\"yG" }{TEXT -1 162 " . You will find that this solid was discussed in the section on plotting using cylinderplot. We will use cylinderplot, which is a 3d -plotter using coordinates " }{XPPEDIT 18 0 "[r,theta,z]" "6#7%%\"rG%& thetaG%\"zG" }{TEXT -1 47 " in parametric form. It may also be used as " }{TEXT 261 41 " cylinderplot(f(r,t),r=g(t)..h(t),t=a..b)" } {TEXT -1 35 " where the surface is defined by " }{XPPEDIT 18 0 "z=f( r,t)" "6#/%\"zG-%\"fG6$%\"rG%\"tG" }{TEXT -1 68 " in cylindrical coor dinates. It is easy to see that we have used " }{TEXT 262 1 "t" } {TEXT -1 14 " instead of " }{XPPEDIT 18 0 "theta" "6#%&thetaG" } {TEXT -1 151 " here. The figure below has been rotated to provide a \+ better viewing angle. In cylindrical coordinates we have the followin g with its output below.\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 88 "roof2:=cylinderplot([r,t,sqrt(4-r^2)],r=0..1,t=0..Pi/2,orientation =[-26,69],color=blue):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 59 "f loor2:=cylinderplot([r,t,0],r=0..1,t=0..Pi/2,color=green):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 63 "cwall2:=cylinderplot([1,t,z],t=0..P i/2,z=0..sqrt(3),color=red):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "display(floor2,roof2,cwall2);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 72 "Adding two more walls gives a figure as the output of the next \+ commands." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 68 "vwall3:=cylind erplot([r,Pi/2,z],z=0..sqrt(4-r^2),r=0..1,color=plum):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 65 "vwall4:=cylinderplot([r,0,z],z=0..s qrt(4-r^2),r=0..1,color=cyan):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 43 "display(floor2,roof2,cwall2,vwall3,vwall4);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 214 "We are almost ready to set up our triple integ ral but first must determine the integrand. This is the one part of t he process that is dealt with as a simple direct substitution. In cyl indrical coordinates we have" }}}{EXCHG {PARA 258 "" 0 "" {TEXT -1 2 " " }{XPPEDIT 18 0 "x=r*cos(theta)" "6#/%\"xG*&%\"rG\"\"\"-%$cosG6#%&t hetaGF'" }}}{EXCHG {PARA 259 "" 0 "" {TEXT -1 2 " " }{XPPEDIT 18 0 "y =r*sin(theta)" "6#/%\"yG*&%\"rG\"\"\"-%$sinG6#%&thetaGF'" }}}{EXCHG {PARA 260 "" 0 "" {TEXT -1 2 " " }{XPPEDIT 18 0 "z=z" "6#/%\"zGF$" }} }{EXCHG {PARA 0 "" 0 "" {TEXT -1 46 "Our integrand in rectangular coor dinates is " }{XPPEDIT 18 0 "f(x,y,z)=x*z" "6#/-%\"fG6%%\"xG%\"yG%\" zG*&F'\"\"\"F)F+" }{TEXT -1 16 " , so in Maple" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "f:=(x,y,z)->x*z;" }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 36 "F:=simplify(f(r*cos(t),r*sin(t),z));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT 263 10 "IMPORTANT:" }{TEXT -1 19 " Note the use of " }{TEXT 264 3 "F*r" }{TEXT -1 70 " for the integrand in our cyl indical coordinate integral! Note that " }{TEXT 266 3 " f " }{TEXT -1 19 " is a function and " }{TEXT 267 2 " F" }{TEXT -1 19 " is an ex pression." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 53 "B:=Tripleint(F *r,z=0..sqrt(4-r^2),r=0..1,t=0..Pi/2);\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "Bval:=value(B);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 40 "With the limits displayed fully, we have" }}}{EXCHG {PARA 0 "" 0 " " {TEXT -1 2 " " }{XPPEDIT 18 0 "Int(Int(Int(x*z,z=(z=0)..(z=sqrt(x^2 -y^2))),x=(x=0)..(x=sqrt(1-y^2))),y=(y=1)..(y=2))=Int(Int(Int(r^2*cos( theta)*z,z=(z=0)..(z=sqrt(4-r^2))),r=(r=0)..(r=1)),theta=(theta=0)..(t heta=Pi/2))" "6#/-%$IntG6$-F%6$-F%6$*&%\"xG\"\"\"%\"zGF-/F.;/F.\"\"!/F .-%%sqrtG6#,&*$F,\"\"#F-*$%\"yGF9!\"\"/F,;/F,F2/F,-F56#,&F-F-*$F;F9F