{VERSION 5 0 "IBM INTEL NT" "5.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 1 }{CSTYLE "" -1 256 "" 0 1 0 128 0 1 0 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 257 "" 0 1 0 128 0 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 258 "" 0 1 0 128 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 259 "" 0 1 128 128 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 260 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 261 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 262 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 263 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 264 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 265 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 266 "" 0 1 128 128 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 267 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 268 "" 0 1 128 128 128 1 0 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 269 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 270 "" 0 1 128 128 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 271 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 272 "" 0 1 128 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 273 "" 0 1 0 0 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 274 "" 0 1 128 0 128 1 0 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 275 "" 0 1 128 0 128 1 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 276 "" 0 1 128 0 128 1 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 277 "" 0 1 0 128 0 1 0 2 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 "Heading 1" -1 3 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 1 0 1 0 2 2 0 1 }{PSTYLE "Heading 2 " -1 4 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 1 0 1 0 2 2 0 1 }{PSTYLE "Normal" -1 256 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 1 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 0 "" 0 "" {TEXT -1 0 "" }{TEXT 257 54 "High School Modul es > Precalculus by Gregory A. Moore\n" }}{PARA 3 "" 0 "" {TEXT -1 4 " " }{TEXT 256 15 "Conic Sections " }{TEXT 277 8 "(Part 1)" }}{PARA 0 "" 0 "" {TEXT -1 208 "\nAn exploration of three of the conic section s - the circle, the parabola and the trivial case of intersecting line s. We will look at the two and three dimensional graphs to see how the se curves are defined.\n" }}{PARA 0 "" 0 "" {TEXT 258 153 "[Directions : Execute the Code Resource section first. Although there will be no \+ output immediately, these definitions are used later in this worksheet .]" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 1 " " }{TEXT 260 7 "0. Code" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 22 "restart; with(plots): " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 239 "sc := 'scaling = constrained':\nt1 := 'thickness = 1':\nt4 := ' thickness = 4':\nl2 := 'linestyle = 2':\nl3 := 'linestyle = 3':\nbl := 'color = COLOR(RGB, .4,.5,.7)':\nbl2 := 'color = COLOR(RGB, .2,.25,.3 5)':\nro := 'color = COLOR(RGB, .9,.6,0)':" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 202 "cone1 := cylinderplot( [r,theta,r],r = 0..5, thet a=0..2*Pi,\n style = patchnogrid):\ncone2 := cylinde rplot( [r,theta,-r],r = 0..5, theta=0..2*Pi,\n style = patchnogrid):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 295 "#_____ ___ LINES _________________________________________\nline1 := spacecu rve([ t,0, t], t=-5..5, color = red):\nline2 := spacecurve([ t,0, -t ], t=-5..5, color = black):\nplnl := implicitplot3d( y = 0 ,x=-5..5, y=-5..5, z=-5..5,\n style=patchnogrid, shading= ZGRAYSCALE ):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 420 "#________ PARABOLA ________ _________________________________\npar := spacecurve([ t, 1-(t^2)/4, \+ 1+(t^2)/4 ],t=-4..4, \n color=blue, thickness=2): \nplnp := plot3d( 2- y, x=-5..5, y= -5..5, \n st yle=patchnogrid, shading=ZGRAYSCALE ):\nxap := spacecurve([ t, 1, 1 \+ ],t=-5..5, color = COLOR(RGB, .3,.7, .3) ):\nyap := spacecurve([ 0, t , 2-t],t=-3..5, color = COLOR(RGB, .3,.7, .3) ):\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 417 "#________ CIRCLES ________________________ _________________\ncir := spacecurve([ 3*cos(t), 3*sin(t), 3 ],t=-4.. 4, \n color=red, thickness=2):\nplnc := plot3d( \+ 3, x=-5..5, y= -5..5, \n style=patchnogrid, color \+ = COLOR(RGB,.67,.67,.75) ):\nxac := spacecurve([ t, 0, 3 ],t=-5..5, c olor = COLOR(RGB,.2,.2,.6) ):\nyac := spacecurve([ 0, t, 3 ],t=-5..5, color = COLOR(RGB,.2,.2,.6) ):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 5 "pln1;" }}}}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 1 " " }{TEXT 263 15 "1. Two Lines " } {TEXT 266 38 " Plane Intersects Cone Through Origin" }{TEXT 267 3 " \+ " }}{PARA 0 "" 0 "" {TEXT -1 174 "\nA double cone is a relatively sim ple three dimensional shape. However, there are several types of curve s which come about as intersections of the cones and a single plane. \+ \n" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 48 "display([cone1, cone2] , orientation = [25,75] );" }}}{PARA 0 "" 0 "" {TEXT -1 159 "\nThis is the simplest intersection. If we cut the cones with a single plane wh ich passes through the axes of symmetry of the cones, we get something like this." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 67 "display([cone 1, cone2, line1,line2, plnl], orientation = [25,75] );" }}}{PARA 0 "" 0 "" {TEXT -1 66 "\nThe intersection of these shapes is a pair of inte rsecting lines." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 61 "display([ cone1, cone2, line1,line2], orientation = [25,75] );" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 62 "display([cone1, cone2, line1,line2], orie ntation = [-50,40] );" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 53 "di splay([line1,line2, plnl], orientation = [33,71] );" }}}{PARA 0 "" 0 " " {TEXT -1 2 "\n " }}}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 1 " " }{TEXT 264 12 "2. Parabola " }{TEXT 268 45 " Plane Intersects Cone Paral lel to Edge " }{TEXT 269 3 " " }}{PARA 0 "" 0 "" {TEXT -1 434 "\nNow we intersect the plane with the cones in a different way. We are goin g to tilt the plane so that its \"slope\" is the same as the edge of t he cone. (For example, we could keep the plane passing through the ori gin where the cones meet, and tilt it until it becomes tangent to the \+ cones, then raise is straight up or down.) The resulting shape is a pa rabola. Notices that the plane only intersects one of the two cones in this case.\n" }}{EXCHG }{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 69 "dis play([ par, plnp, cone1, cone2,xap,yap ], orientation = [25,75] );" }} }{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 55 "display([ par, cone1, cone2 ], orientation = [25,75] );" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 55 "display([ par, plnp,xap,yap ], orientation = [35,75] );" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 70 "display([ par, plnp,xap,yap \+ ], orientation = [ -90,135],axes = none );" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 2 "\n " }}}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 1 " " }{TEXT 265 18 "3. Parabola " }{TEXT 272 27 "Equat ion & Standard Graph " }{TEXT 273 19 " " }}{PARA 0 "" 0 "" {TEXT -1 1 "\n" }{TEXT 275 26 " Plain Vanilla Parabola" } {TEXT -1 96 "\n\nHere is a very simple parabola and some variations th at occur when shifting and stretching it." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "plot( x^2, x = -3..3, t4,bl);" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 115 "display( plot( (x-3)^2 + 5, x = -3..6, y = 0 ..20, t4,bl),\n plot( x^2, x = -3..6, y = 0..20, t1,bl2, l2) ) ;" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 109 "display( plot( 3*x^2, x = -3..3, y = 0..20, t4,bl),\n plot( x^2, x = -3..3, y = 0. .20, t1,bl2, l2) );" }}}{PARA 0 "" 0 "" {TEXT -1 3 "\n\n\n" }{TEXT 276 21 " Formal Definition" }{TEXT -1 152 "\n\nHere is the formal d efinition of a parabola... as the set of points equidistant between a \+ point, (0,1) in this case, and a line, y = -1 in this case.\n" }} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 430 "display( plot( (1/4)*x^2, x = -3..3,t4,bl),\n plot( [[-3,-1],[3,-1]], t4, ro, l3),\n \+ pointplot( [0,1], ro, symbol = diamond, symbolsize = 30),\n \+ plot( [[-1,-1],[-1,1/4],[0,1]], t1, color = green, l2),\n pl ot( [[-2.5,-1],[-2.5,25/16],[0,1]], t1, color = green, l2),\n \+ plot( [[ 1,-1],[1,1/4],[0,1]], t1, color = green, l2),\n plot( [[ 2.5,-1],[ 2.5,25/16],[0,1]], t1, color = green, l2) );" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 2 "\n " }}}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 1 " " }{TEXT 261 12 "4. Circle " }{TEXT 270 60 " Plane Intersects Cone Perpindicula r to Axis of Cone" }{TEXT 271 3 " " }}{PARA 0 "" 0 "" {TEXT -1 180 " \nAnother way to intersect the cones is with a plane which is perpindi cular to the axes of symmetry of the cones - much like chopping a carr ot with a knife. The result is a circle.\n" }}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 60 "display([ cir, plnc, cone1, cone2], orientation = [ 33,72] );" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 69 "display([ cir, plnc, cone1, cone2,xac,yac ], orientation = [48,63] );" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 56 "display([ cir, plnc, xac,yac ], ori entation = [43,62] );" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 55 "di splay([ cir, plnc, xac,yac ], orientation = [90,0] );" }}}{PARA 0 "" 0 "" {TEXT -1 2 "\n " }}}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 1 " " } {TEXT 262 21 "5. Circle " }{TEXT 274 27 "Equation & Standar d Graph " }}{PARA 0 "" 0 "" {TEXT -1 90 "\nCircles are very simple si nce one looks like another - except for the size and position.\n" }} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 60 "implicitplot( x^2 + y^2 = 2^ 2, x = -3..3, y=-3..3,t4,bl,sc);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 176 "display( implicitplot( x^2 + y^2 = 2^2, x = -3..3, y=-3..3, t1,bl2, l2),\n implicitplot( (x-2)^2 + (y-4)^2 = 2^2 , x = -3..6,y=-3..7,\n t4,bl,sc));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 176 "display( implicitplot( x^2 + y^2 \+ = 2^2, x = -3..3, y=-3..3, t1,bl2, l2),\n implicitplot( (x+2) ^2 + (y+3)^2 = 3^2, x = -6..6,y=-6..3,\n t4,bl,s c));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 " " {TEXT -1 2 "\n " }}}{PARA 0 "" 0 "" {TEXT 259 35 "\n \251 20 02 Waterloo Maple Inc" }}}{MARK "0 1" 32 }{VIEWOPTS 1 1 0 1 1 1803 1 1 1 1 }{PAGENUMBERS 0 1 2 33 1 1 }