Chapter 14.3, Problem 29E

Converting to Polar Coordinates:

In Exercises 29–-32, use polar coordinates to set up and evaluate the double integral

${\displaystyle {\int }_R{\displaystyle \int f(x,y)dA}}$

$\begin{array}{l}f(x,y)=x+y\\ R:x^2+y^2\le 36,x\ge 0,y\ge 0\end{array}$