[tex]f(x)=\sin(\frac{px}{2})\\[/tex](adsbygoogle = window.adsbygoogle || []).push({});

[tex]a_0=0[/tex]

[tex]a_n=0[/tex]

[tex]b_n=\frac{1}{\pi}\int_{-\pi}^{\pi}\(\sin(\frac{px}{2}))\sin(nx)dx=\frac{1}{2\pi}[\sin(\frac{p\pi}{2}-n\pi)-\sin(\frac{-p\pi}{2}+n\pi)]+\frac{1}{2\pi}[\sin(\frac{p\pi}{2}+n\pi)-\sin(\frac{-p\pi}{2}-n\pi)][/tex]

i used trig identetied to splt into two cosines

andi solved

but i got sines

i need an expression of cosines to do cos nx=(-1)^n

i need to have a simple linear fracture without cosines or sines

i cant transform it here in the needed form

?

and if thinking thurely then i see that i have a trig function on a simetric period

so its zero

so the foorier representation of the given function is zero

?

where is the mistake

it cant be zero

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# Homework Help: Foorier represtaion of this function

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