## anonymous 5 years ago i need help with a problem in multivariable calc Calculate the double integral. Calculate the double integral. x/(x^2 + Y^2) under the region (in the x y plane R = x:[1,2] and y:[0,1] How would you get the value of the integral... i tried integration by parts but i thinks it is getting a little too complicated whats the solution?

1. amistre64

would you solve for x while y is a constant; and then solve for y while x is a constant ? I have enough issues trying to solve single integrals :)

2. amistre64

FSU eh.... im currently going thru PHCC.... down here by USF :)

3. anonymous

well wouldnt is simplify the integral of that would be 1/2 the ln(x^2 +y^2) right if i take the integral w/ respect to x first then i plug in the bounds then i integrate with respect to y thats when it gets messy

4. anonymous

Hey you should solve it using polar coordinates.. set $x=r \cos \theta, y=r \sin \theta \implies x^2+y^2=r^2$