I've got parts of this problem but I'm stuck on some of the integration. See attached. Thanks!
First, since an interval is 0 to [itex]\pi[/itex] what are you integrating over 0 to [itex]\pi/2[/tex]?
Second, since cos x is positive from 0 to [itex]\pi/2[/itex] and negative from [itex]\pi/2[/itex] to [itex]\pi[/itex], you can replace |cos(x)| with
cos(x) from 0 to [itex]\pi/2[/itex] and with -cos(x) for [itex]\pi/2[/itex] to [itex]\pi[/itex].
I changed the interval I was integrating over b/c that's part of the equation. You can't integrate from -l to l so you change it to 0 to l where l is half of the fundamental period and instead of multiplying the integral by 1/l, I changed it to 2/l. Is it easier to just integrate from -l to l?
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