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joemama69
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Homework Statement
Use polar coords to evaluate the double integral x3 + xy2dydx from y = -(9-x2)1/2 to (9-x2)1/2, and x = 0 to 3
Homework Equations
The Attempt at a Solution
So the region is a half circle of radius 3, centered @ the origin, with only the possitive x side, (right side of circle)
x = rcosQ, y = rsinQ
the integral is r3cos3Q + r3cosQsinQ drdQ
after integration with respect to r i get and pluging in the limits
84/4 cos^3 Q + 81/4 cosQsinQ dQ
i looked up the integrals of cos^3Q in the back of my book and it is quite complex. Have i made any mistakes thus far, and is there an easier way to evaluate it