(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Derive the following:

y = (cosxsin2x)^{-2}

2. The attempt at a solution

Basically I saw this as a power rule with two products in the middle.

So y = -2 (cos2cos2x-sinxsin2x)^{-1}

But the correct answer is completely different, it's:

4(3sin^{2}x - 1) all over

cos^{2}xsin^{3}2x

Could someone please go through the steps to get to the correct solution? Thanks in advance!

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# Trigonometric derivative: power rule + product rule

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