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110 " To examine the long term behaviour of the simple pendulum modell
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To prove the system is reversible substitute" }}{PARA 0 "" 0 "" {OLE 
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{TEXT -1 29 "into the system of equations." }}}{EXCHG {PARA 0 "> " 0 "
" {MPLTEXT 1 0 18 "F:=diff(x(t),t)=y;" }}{PARA 11 "" 1 "" {XPPMATH 20 
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{MPLTEXT 1 0 29 "G:=diff(y(t),t)=(g/l)*sin(x);" }}{PARA 11 "" 1 "" 
{XPPMATH 20 "6#>%\"GG/-%%diffG6$-%\"yG6#%\"tGF,*(%\"gG\"\"\"%\"lG!\"\"
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{TEXT -1 103 "These two equations are identical to the original two eq
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