Finding the Area Enclosed by a Polar Curve

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Can someone please help me on this question. I tried to solve it by integrating 0.5*(1-3sin(θ)^2 from -Pi/2 to 0 but I didnt get the answer.
 

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amninder15 said:
Can someone please help me on this question. I tried to solve it by integrating 0.5*(1-3sin(θ)^2 from -Pi/2 to 0 but I didnt get the answer.

Why did you choose ##-\frac \pi 2## to ##0##? Just guessing? Have you drawn a sketch? Do you know what ##\theta## give negative ##r## values for the inner loop?
 
Yea I made some silly mistake I think It goes from sin^-1(1/3) to Pi-sin^-1(1/3). But that looks ugly. Am I on right path.
 

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Your graph is correct for ##\theta## varies between 0 and 2pi. Now, generally how do you find the area of a polar region?
 
amninder15 said:
Yea I made some silly mistake I think It goes from sin^-1(1/3) to Pi-sin^-1(1/3). But that looks ugly. Am I on right path.

Yes. Those are the correct limits. Ugly or not, just plow ahead and you will get one of the answers listed.
 
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