How Do I Set Up a Double Integral for a Cylinder's Volume in Polar Coordinates?

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whynot314
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Homework Statement


I want to convert this into polar and use double integral to find the volume of the solid in this region. I just need help setting this up
region
Q: x^2+y^2≤9, 0≤z≤4
I know this is a cylinder with a height of 4.
I am just having trouble incorporating this height into the integral.

The Attempt at a Solution


∫_0^2π▒〖∫_0^3▒4 r〗 drd(theta)
this is currently what I have
 
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"integral from 0 to 2pi" then integral 0 to 3. then 4 rdrdθ
 
This is correct.
There is a cylinder with height 4. When using a double integral to find the volume of a solid object, you can set it up with the "Top - Bottom" as the function to integrate. This can also be done by adding in a third integral and integrating 1.
[itex]\int_0^{2\pi} \int_0^3 \int_0^4 (1)dV[/itex], where [itex]dV[/itex] is [itex]rdzdrd\theta[/itex].
[itex]=\int_0^{2\pi} \int_0^3 (4) (r)drd\theta[/itex]
You can also check this by using the formula for the volume of a cylinder which is [itex]\pi r^2h[/itex]
 
[itex]\int^\3_\0[/itex]