# Math Help - Integrate

1. ## Integrate

Im having trouble with my limits, and whether or not im on the right direction

My question is:
Let R be the region in the first quadrant bounded by the line y=x and the curve
x^4 + (xy)^2 = y^2.

My double integral is
(1+ x^2 + y^2)^-2 dA

heres what im doing so far..
and then evaluate..Am i right, limits correct and everything

IN THE FUNCTION, SHOULD BE R/(1 + R^2)^2

2. $\displaystyle x^4 + (xy)^2 = y^2\rightarrow r^2=tan^2(\theta)$

$\displaystyle y=x\rightarrow tan(\theta)=1$

$\displaystyle \int\int \frac{r}{(1+r^2)^2}drd\theta$

3. thanks for the help so far,