This is the problem with the answer
This is my attempt at solving it
Evidently, my attempt is wrong as the right answer is $36 \pi$. Why are my bounds wrong?
Edit tried to use math jax: $$ \oint_C \left(3y-e^{\sin x}\right)\, dx + \left(7x+\sqrt{y^4+1}\right) \ dy $$
I did this: $$ \int_{-3}^3 \int_{-3}^{\sqrt{9-y^2}}\ \ 4 \ dx dy $$
The correct answer is $36 \pi$ but this yields $18 \times (4+\pi)$. Why is it wrong?