i have the equation (x+n2pi) but don't know where to go from their
How did you get x+n2pi?
f(x + P) = f(x)
the periodic function of cosine is 2pi? no?
What you've written makes no sense at all! What do you mean by
"sin-(cos(7pi/5) (arcsin)"?? And what does that have to do with an inverse function?
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