Please give me a help to find the answer for the following Fourier series question:

Find the steady state oscillation corresponding to

(d^2y)/(dx^2)y + c dy/dx + y = r(t) , where c > 0 and

r(t)=(pi*t)/4 if (-pi)/2<t<(pi/2)

r(t)=[pi*(pi-t)]/4 if (pi/2)<t<[(3*pi)/2]

and r(t)=r(t+2*pi)

{the same is you can see the attached file here}

please be kind enough to help this my homework question.

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