How Do You Determine the Limits for r and θ in a Cylindrical Coordinate System?

J Galt
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What are the r and θ limits for the triple integral of y where there's a parabloid cylinder x=y^2 and planes x+z=1 and z=0?

I rearranged x+z=1 to get z=1-x => so 1-rcosθ; 0 ≤ z ≤ 1-rcosθ
but I don't know how to get the limits for θ or r. How do I do this?
 
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Welcome to PF!

Hi J Galt! Welcome to PF! :smile:

(are you trying to find the volume … you didn't say?)

Just because there's a cylinder, that doesn't mean you have to use cylindrical coordinates. :rolleyes:

Use whatever method makes it easier! :smile:

In this case, I'd use horizontal (z = constant) slices, 'cos I think that's easiest! :smile:
 
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