{VERSION 2 3 "APPLE_68K_MAC" "2.3" }
{USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 
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{CSTYLE "" -1 257 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 }{CSTYLE "" -1 258 
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{SECT 0 {EXCHG {PARA 256 "" 0 "" {TEXT -1 37 "From Three Dimensions to
 Two and Back" }}{PARA 0 "" 0 "" {TEXT -1 113 "\nThe cell below illust
rates how Maple can be used to find the shadow produced by an object l
ocated at the point  " }}{PARA 0 "" 0 "" {TEXT 256 13 "P = (2, 1, 1)" 
}{TEXT -1 54 "  illuminated by a light source located at the point  " 
}{TEXT 257 15 "S = (1, -2, 8)." }{TEXT -1 4 "    " }{TEXT 258 15 "Eval
uate it now" }{TEXT -1 1 "." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 95 "P := [2, 1, 1]:\nS := [1, -2
, 8]:\n\nanswer := solve(evalm(S[3] + t * (P[3] - S[3]) = 0), \{t\}); \+
  " }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 106 "[subs(answer, S[1] + t * (P[
1] - S[1])),                         subs(answer, S[2] + t * (P[2] - S
[2]))]; " }}}}{MARK "1 0 0" 0 }{VIEWOPTS 1 1 0 1 1 1803 }