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{SECT 0 {EXCHG {PARA 18 "" 1 "" {TEXT -1 49 "Harmonic Oscillators --- \+
with and without damping" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 52 "Look \+
at an oscillator without damping: y'' + 8 y = 0" }}{PARA 0 "> " 0 "" 
{MPLTEXT 1 0 0 "" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 36 "diff_eqn := D(D
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,&---%#@@G6$%\"DG\"\"#6#%\"yG6#%\"tG\"\"\"-F/F0\"\")\"\"!" }}}{EXCHG 
{PARA 0 "" 0 "" {TEXT -1 29 "Define the initial conditions" }{MPLTEXT 
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\"\"!\"\"\"/--%\"DG6#F(F)F+" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 
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{TEXT -1 118 "Plot the solution.  Note that it does not appear to have
 its amplitude decayin in time.  (In fact, we can prove this.)" }
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