Hi, I need help with this problem(adsbygoogle = window.adsbygoogle || []).push({});

Evaluate the given integral by changing to polar cordinates

∫∫xydA where D is the disc with centre the origin and radius.

My solution so far.

I believe this would give a circle with radius 3 in xy plane. And then x=r*cos(θ) and y=r*sin(θ)

So ∫(∫((r*cos(θ)*r*sin(θ))*r,r,0,3),θ,0,2∏)

But the result is suppose to be zero.

What am I doing wrong?

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# Homework Help: Double integral polar cordiantes

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