Here are a few problems i dont know where to start, basically because my trig teacher doesnt teach...but anyways if you have any ideas on any of them, please post(adsbygoogle = window.adsbygoogle || []).push({});

tan(x+PI) - tan(x-PI)= 2 tan x

^ verify the identity

cos(x+y)cos(x-y) = cos^2 x - sin^2 y

^ verify identity

sin(arctan2x-arccosx)

^write as an algebraic expression

and

cos(x + PI/4) - cos(x- PI/4) = 1

^find all solutions

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# Homework Help: A few trig homework questions

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