# Area of circle using integration

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1. Jan 13, 2016

### PhysicsBoyMan

1. The problem statement, all variables and given/known data
2. Relevant equations

http://postimage.org/] [/PLAIN] [Broken]
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3. The attempt at a solution

Found width of that rectangle. Multiply times delta h. My question is, why is the integral from -3 to 3? When I try to evaluate the integral by going h(3) - h(-3) I get 0-0. If you use 3 or -3 for h you get 0. I don't understand how to evaluate this integral?

Last edited by a moderator: May 7, 2017
2. Jan 13, 2016

### axmls

You go from -3 to 3 because from the picture, the center is h = 0. You'll have to show your work on the integral so we can evaluate it for errors.

3. Jan 13, 2016

### PhysicsBoyMan

Ooops I forgot to take the actual integral. I was just plugging in h = -3 and h = 3 into that solution. Thanks.