- #1
manjum423
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Homework Statement
Let S be the part of the cylinder of radius 9 centered about z-axis and bounded
by y >= 0; z = -17; z = 17. Evaluate
[itex]\iint xy^2z^2[/itex]
Homework Equations
The Attempt at a Solution
So I use the equation [itex]x^2 + y^2 \leq 9[/itex], meaning that r goes from 0 to 3
Since [itex]y \geq 0[/itex], θ goes from 0 to ∏
So the integral looks like this:
[itex]\int_0^∏ \int_0^3 \int_{-17}^{17} (rcosθ)(rsinθ)^2 z^2 r dzdrdθ[/itex]
And I get:
[itex]\int_0^∏ \int_0^3 \int_{-17}^{17} r^4 cosθsin^2θ z^2 dzdrdθ[/itex]
I'm having trouble evaluating this integral because for the [itex]\int_0^∏ cosθsin^2θ [/itex]part. I get 0 (When u=sinθ by u-substitution and you get [itex](1/3)sin^3θ [/itex] from 0 to ∏)
Basically I would like to know if my limits and my setup is correct, and if anyone can help me out with a solution I would be grateful.