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

[itex]\int^{\pi}_{0}[/itex] [itex]\int^{1-sin\theta}_{0}[/itex] r[itex]^{2}[/itex] cos[itex]\theta[/itex] drd[itex]\theta[/itex]

I keep getting an answer of 0 but i am most certain that i am getting my trig messed up somewhere.

1/3 [itex]\int^{\pi}_{0}[/itex] r[itex]^{3}[/itex] cos[itex]\theta[/itex][itex]d[itex]\theta[/itex] from 0 to 1-sin\theta

then i get

1/3 [itex]\int^{\pi}_{0}[/itex] (1-sin\theta)^3 cos\theta d\theta

I then use substitution,u for 1-sin\theta then get 1/3 times -1/4(u)^4

substitute back the 1-sin\theta and evaluate from 0 to \pi and I keep getting zero please help thanks

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# Homework Help: Evaluate the double integral

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