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Double angle formula

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Please prove the following identity without using the quotient identity:
sin(2x)/cos(2x) = 2tan(x)/1-tan²(x)

I need to use the double angle formulas for sine and cosine.

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Solution Summary

This solution shows how to prove the identity of sin(2x)/cos(2x) = 2tan(x)/1-tan²(x) using double angle formulas.

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