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

"Find the area of the region described: The region that is enclosed by the rose r=4cos3[theta]"

2. Relevant equations

A= [integral] (1/2)r^2 d[theta]

3. The attempt at a solution

I'll use Q as [theta]..

I'm not really sure, but I set up (1/2) [integral] (16(cos^2)3Q) dQ

.. then I thought we were supposed to use the identity (cos^2)Q = (1/2)(1+cos2Q), but every time I substitute this in and integrate, I get 8[pi] instead of 4[pi], the correct answer. What am I doing wrong?

Thank you so much :]

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# Homework Help: Finding area in polar coordinates

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