How Do You Compute the Fourier Series for |sin(x)| Over the Interval (-1,1)?

Dassinia
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Hello,
Find the Fourier serie of f(x)=|sin(x)| on the interval (-1,1)

I'm just a little confused, does that mean that I have to integrate from -1 to 1 to find the coefficients ? Because the formula of the coefficients is in terms of the period T, for this function the period is pi. Or do I have to consider it only in -1,1 and take the period T=2 ?

Thanks
 
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For a homework problem, it seems like the given interval might be a typo or the function was supposed to be ##\lvert \sin \pi x \rvert##; however, there's no real reason the interval couldn't be (-1, 1) for the given function. I'd check with your instructor if I were you.
 
It's not a homework, it's an exercise in a previous exam..
the exam is tomorrow and I just saw this exercise.. :frown:

EDIT: I sent an email to an instructor, and I had my answer !
 
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