# Double Integral

• February 11th 2009, 04:26 PM
eigenvector11
Double Integral
Calculate the double integral:

x/(x^2 + y^2)dA, R = [1,2] x [0,1].

I'm not sure how to iterate this integral and proceed onwards. Any ideas?

• February 12th 2009, 07:48 AM
Krizalid
This is quite straightforward, it's just $\int_{0}^{1}{\int_{1}^{2}{\frac{x}{{{x}^{2}}+{{y}^ {2}}}\,dx}\,dy}.$

The inner integral is easy to solve and the remaining integral can be tackled by simple partial integration. (See my signature.)