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{SECT 0 {EXCHG {PARA 257 "" 0 "" {TEXT 256 44 "Example of  LRC system \+
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" }}{PARA 0 "" 0 "" {XPPEDIT 18 0 "d^2 *y/dt^2+2*alpha dy/dt+y=f(t)" "
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}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 40 "The period in the periodic exten
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" {XPPMATH 20 "6#>%\"aG\"\"$" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" 
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;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%#cnGR6#%\"nG6\"6$%)operatorG%&a
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{PARA 0 "" 0 "" {TEXT -1 75 "The fourer coefficient of the solution to
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{MPLTEXT 1 0 49 "eta:=n->cn(n)/(-(2*Pi*n/a)^2+4*Pi*I*alpha*n/a+1);" }}
{PARA 11 "" 1 "" {XPPMATH 20 "6#>%$etaGR6#%\"nG6\"6$%)operatorG%&arrow
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t  the solution into a function. The physical value of q is the real p
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{TEXT -1 47 "series the terms n=-N..N and pick a value for N" }}}
{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 5 "N:=5;" }}{PARA 11 "" 1 "" 
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79 "q:=x->eta0+sum(Re(eta(n)*exp(2*Pi*I*n*x/a)+eta(-n)*exp(-2*Pi*I*n*x
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