# Question about Volume of Solids

1. Dec 11, 2006

### Gauss177

I'm having trouble with problems where you have to find the volume of a solids that are not solids of revolution. Can someone help me with these problems and also tell me a general way of approaching these problems? Thanks

1. The problem statement, all variables and given/known data
A hole of radius r is bored through the center of a sphere of radius R > r. Find the volume of the remaining portion of the sphere.

2. The problem statement, all variables and given/known data
The base of S (the solid) is an elliptical region with boundary curve $$9x^2 + 4y^2 = 36$$. Cross-sections perpendicular to the x-axis are isosceles right triangles with hypotenuse in the base.

2. Dec 11, 2006

### StatusX

For 1, that is a solid of revolution, try drawing it. For 2, it is very similar to integrating solid of revolution, only instead of adding up circles you are adding up triangles. Again, if you can picture the shape it shouldn't be too hard.