Calculus of Disks, Washers, Slicing -- Example 2 Using Washers

This method is fairly simple, and involves identifying an inner and outer radius.
It is very similar to the method of disks.
I will upload more involved examples, but for now these are the basics.

 

If you have any questions please post it in the comment box.  If it is substantial I'll make another post about it, if not I will just reply as a comment. 

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