Triple Integral in Cylindrical Coords

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DTskkaii
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Homework Statement


Construct a triple integral in cylindrical coords to find the volume of the cone r=z, where the height (z value) is limited by z=L.
Should be in the form => {int[b,a] int[d,c] int[f,e]} (r) {dr dtheta dz}
(Sorry for weird formatting above, brackets purely to make terms more discernible)
Then evaluate using this order of integration to find volume.


Homework Equations


Volume of a cone => V=[(pi)(a)^2(L)]/3
In a cylindrical coord system, r=z describes an inverted cone of infinite height


The Attempt at a Solution


Currently working on an attempt, but if someone could help out with the understanding, that would be great. It doesn't immediately make a lot of sense to me.
i.e. r=z gives infinite height, but the volume is limited by L, so how do I find limits for that? Also can't see any immediate limits for theta in this situation.
 
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DTskkaii said:
r=z gives infinite height

What do you mean? The limits you are given are [itex]0 \ge z \ge L[/itex] and [itex]0 \ge r \ge z[/itex]. Everything is bounded here. Try drawing a picture to see why the limits are as they are.
 
clamtrox said:
What do you mean? The limits you are given are [itex]0 \ge z \ge L[/itex] and [itex]0 \ge r \ge z[/itex]. Everything is bounded here. Try drawing a picture to see why the limits are as they are.

I think you mean: [itex]0 \le z \le L[/itex] and [itex]0 \le r \le z[/itex]
 
sharks said:
I think you mean: [itex]0 \le z \le L[/itex] and [itex]0 \le r \le z[/itex]

Whoops! Indeed L>0 :)