Chapter 17.4, Problem 32E

Line integrals Use Green’s Theorem to evaluate the following line integrals. Assume all curves are oriented counterclockwise. A sketch is helpful.

32. ${\displaystyle \underset{C}{\oint }\langle \sin y,x\rangle }\cdot dr$, where C is the boundary of the triangle with vertices (0, 0) $\left(\frac{\pi }{2},0\right)$, 0) and $\left(\frac{\pi }{2},\frac{\pi }{2}\right)$