{VERSION 2 3 "SUN SPARC SOLARIS" "2.3" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 }{CSTYLE "2D Math" -1 2 "Times" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 }{CSTYLE "2D Comment" 2 18 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 256 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 258 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 }{CSTYLE "" -1 259 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 }{CSTYLE "" -1 260 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 261 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 }{CSTYLE "" -1 262 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 263 "" 1 14 0 0 0 0 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 }{CSTYLE "" -1 267 "" 0 1 0 0 0 0 1 0 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 }{CSTYLE "" -1 269 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" 18 270 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 271 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" 18 272 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 273 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 274 "" 1 14 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 275 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }{CSTYLE " " -1 276 "" 1 14 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 277 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }{PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 " " 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 } {PSTYLE "Heading 1" 0 3 1 {CSTYLE "" -1 -1 "" 1 18 0 0 0 0 0 1 0 0 0 0 0 0 0 }1 0 0 0 6 6 0 0 0 0 0 0 -1 0 }{PSTYLE "Heading 2" 3 4 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 4 4 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 256 1 {CSTYLE "" -1 -1 "" 1 18 0 0 0 0 0 1 0 0 0 0 0 0 0 }3 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 257 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 258 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 259 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 260 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 261 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 262 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 263 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 264 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 265 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 266 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 267 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 268 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 269 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "" 0 270 1 {CSTYLE "" -1 -1 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }} {SECT 0 {PARA 256 "" 0 "" {TEXT -1 17 "Standard Surfaces" }}{PARA 0 " " 0 "" {TEXT -1 0 "" }}{SECT 0 {PARA 3 "" 0 "" {TEXT -1 74 "We study t he standard surfaces - cylinders, paraboloids, cones, ellipsoids" }} {PARA 268 "" 0 "" {TEXT -1 4 "From" }{TEXT 266 8 " Options" }{TEXT -1 8 " choose " }{TEXT 267 12 "Plot Display" }{TEXT -1 17 " and then choo se " }{TEXT 268 7 "Window." }}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 47 "Cyl inders - equations with one variable missing" }}{EXCHG {PARA 0 "" 0 " " {TEXT 256 22 "Consider the equation " }{XPPEDIT 18 0 "z=x^2/4" "/%\" zG*&%\"xG\"\"#\"\"%!\"\"" }{TEXT 263 162 " . Note the y variable is missing so this is a cylinder with axis parallel to the y axis. Since it is of the form z=.. we may plot it using the plot3d command" }} {PARA 0 "> " 0 "" {MPLTEXT 1 0 121 "restart;\nplot3d( x^2/4, x=-2..2, \+ y=-2..2, orientation=[40,65], \n axes=boxed, style = patch, tit le = `x^2 = 4z` ) ;" }}}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 12 "Parabolo ids " }}{EXCHG {PARA 257 "" 0 "" {TEXT -1 15 "One example is " } {XPPEDIT 18 0 "z = x^2/4 + y^2/9 " "/%\"zG,&*&%\"xG\"\"#\"\"%!\"\"\"\" \"*&%\"yG\"\"#\"\"*F)F*" }{TEXT -1 1 " " }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 156 "plot3d( x^2/4 + y^2/9, x=-3..3, y=-3..3, axes=boxed, view=0.. 1,\n title = `z=x^2/4 + y^2/9`, style=patchcontour, \+ orientation=[45,75] );" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 258 "" 0 "" {TEXT -1 196 "Intersections of this surface with any verti cal plane through the origin is a parabola as seen by rotating this pi cture so that phi=90 (outer boundary is a parabola and is the intersec tion of the " }}{PARA 269 "" 0 "" {TEXT -1 52 "paraboloid with a verti cal plane through the z axis." }}{PARA 270 "" 0 "" {TEXT -1 237 "\nThe intersection of this surface with any horizontal plane is an ellipse \+ as seen by rotating picture so that phi =0 (the contour lines are elli pses which are the curves of intersection).\n\nSo this surface is name d an elliptic paraboloid." }}}{SECT 1 {PARA 4 "" 0 "" {TEXT -1 6 "Cone s." }}{EXCHG {PARA 259 "" 0 "" {TEXT -1 25 "One example of a cone is \+ " }{XPPEDIT 18 0 "z^2 =x^2/4 + y^2/9" "/*$%\"zG\"\"#,&*&%\"xG\"\"#\"\" %!\"\"\"\"\"*&%\"yG\"\"#\"\"*F+F," }{TEXT -1 24 " . We plot it using t he " }{TEXT 258 15 "implicitplot3d " }{TEXT -1 7 "command" }}{PARA 0 " > " 0 "" {MPLTEXT 1 0 187 "with(plots):\nimplicitplot3d( z^2 = x^2/4 + y^2/9, x=-2..2, y=-3..3, z=-2..2,\n style=patchnogrid, axes=boxed , grid=[10,10,10], \n title=`z^2 = x^2/4 + y^2/9`, orientation=[60 ,75] );" }}}{PARA 263 "" 0 "" {TEXT -1 0 "" }}{PARA 260 "" 0 "" {TEXT -1 44 "We obtain a poor picture because of the way " }{TEXT 259 14 "im plicitplot3d" }{TEXT -1 98 " works. To improve the picture one would h ave to take a finer grid. Read about the options later. " }}{PARA 261 "" 0 "" {TEXT -1 22 "Instead we will use a " }{TEXT 260 26 "parametric representation " }{TEXT -1 37 "of this cone to obtain a better plot. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{EXCHG {PARA 262 "" 0 "" {TEXT -1 55 "Using something similar to polar coordinates, the cone " } {XPPEDIT 18 0 "z^2 = x^2/4 + y^2/9" "/*$%\"zG\"\"#,&*&%\"xG\"\"#\"\"%! \"\"\"\"\"*&%\"yG\"\"#\"\"*F+F," }{TEXT -1 90 " has parametric repres entation x = 2r cos(t), y = 3r sin(t), z=+ - r, r=0.." } {XPPEDIT 18 0 "\\infinity" "I)infinityG6\"" }{TEXT -1 11 ", t=0..2 " }{XPPEDIT 18 0 "pi" "I#piG6\"" }{TEXT -1 1 " " }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 166 "plot3d( [2*abs(r)*cos(t), 3*abs(r)*sin(t), r], t=0.. 2*Pi, r=-1..1,\n title=`z^2 = x^2/4 + y^2/9`, style=patchcontou r,\n axes=boxed, orientation=[60,75] );" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 264 "" 0 "" {TEXT -1 107 "To obtain a realistic \+ view of the cone choose the CONSTRAINED option from the Projection men u of the plot. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 265 "" 0 "" {TEXT -1 119 "If we flatten this picture so that phi=0 then we see tha t sections of this surface with horizontal planes are ellipses." }}} {SECT 1 {PARA 4 "" 0 "" {TEXT -1 10 "Ellipsoids" }}{PARA 266 "" 0 "" {TEXT -1 31 "One example of an ellipsoid is " }{XPPEDIT 18 0 "x^2/4 + \+ y^2/9 + z^2/4 =1 " "/,(*&%\"xG\"\"#\"\"%!\"\"\"\"\"*&%\"yG\"\"#\"\"*F( F)*&%\"zG\"\"#\"\"%F(F)\"\"\"" }{TEXT -1 124 ". Ellipsoids are spheres which have been deformed through stretching in some directions as wil l be seen from the plot below\n" }}{EXCHG {PARA 267 "" 0 "" {TEXT -1 20 "Plot obtained using " }{TEXT 261 14 "implicitplot3d" }{TEXT -1 155 " is not very good. Instead, we plot the surface using its paramet ric representation. Motivated by spherical coordinates, the parametric representation for " }{XPPEDIT 18 0 "x^2/4 + y^2/9 + z^2/4 =1" "/,(*& %\"xG\"\"#\"\"%!\"\"\"\"\"*&%\"yG\"\"#\"\"*F(F)*&%\"zG\"\"#\"\"%F(F)\" \"\"" }{TEXT -1 4 " is\n" }{TEXT 269 81 "x=2 sin(p) cos(t) , y= 3 s in(p) sin(t), z=2 cos(p), p =0.." }{XPPEDIT 270 0 "pi" "I#piG6\"" }{TEXT 271 9 ", t=0..2" }{XPPEDIT 272 0 "pi" "I#piG6 \"" }{TEXT 273 1 " " }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 175 "plot3d( [2* cos(t)*sin(p), 3*sin(t)*sin(p), 2*cos(p)], t=0..2*Pi,\n p = 0.. Pi, axes=boxed, style=patch, orientation=[150,64],\n title=`x^2 /4 + y^2/9 + z^2/4 = 1` );" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 262 144 "The plot is misleading - it looks like a sphere. Actually, some direc tions are stretched more than others. To obtain a realistic picture ch oose " }{TEXT 274 11 "Constrained" }{TEXT 275 10 " from the " }{TEXT 276 11 "Projection " }{TEXT 277 140 "menu of the plot window. Also, if the picture is flattened so that phi=0 then one sees that horizontal \+ sections of this surface are ellipses" }{TEXT -1 1 "." }}}}}{MARK "2 5 " 0 }{VIEWOPTS 1 1 0 1 1 1803 }