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**Natalie11391** Ahh whoops! Ok, so I checked and I had made a stupid mistake but I carried on with $\displaystyle 4x^2y^3+2x^4y+2y^5$ in the integrand and converted to polars

$\displaystyle x=acos\theta$

$\displaystyle y=asin\theta$

$\displaystyle dxdy=adad\theta$

but I ended up with

$\displaystyle 1/7 \pi a^7(2cos^2asin^3a+cos^4asina+sina)$

which I'm pretty sure must be wrong. I'm not sure if I'm just being stupid or if I've been awake too long but if you can see where I've gone wrong, could you point it out for me? Thanks!