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Further GCSE Maths Help

Prove that

Sin THETA - Sin^3THETA / Cos^3 THETA = Tan THETA

I assume you use the rule that Sin THETA / Cos THETA = Tan THETA but apart from that I'm stuck
Reply 1
So Sin theta and sin^3 theta are both over cos^3 theta or just sin^3 theta/cos^3 theta?
Reply 2
Original post by Xzerzes
So Sin theta and sin^3 theta are both over cos^3 theta or just sin^3 theta/cos^3 theta?


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Photo on 30-04-2016 at 11.40 a.m..jpg
Reply 4
sinx(1sin2x)cos3x \displaystyle \frac{\sin x(1-\sin^2 x)}{\cos^3 x} .
Remember that sin2x+cos2x1 \sin^2 x + \cos^2 x \equiv 1 .

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