Area of a rose petal using Green's Theorem

Use Green's theorem to compute the area of one petal of the 16-leafed rose defined by r = 13sin(8t).

It may be useful for recall that the area of a region D enclosed by a curve C can be expressed as A = (1/2)*integral(xdy - ydx).

**Attempt at a solution:**

I've got that the limit of theta should be from 0 to pi/8.

x = 13sin(8t)*cos(t)

y = 13sin(8t)*sin(t)

dx = [104cos(8t)*cos(t) - 13sin(8t)*sin(t)]dt

dy = [104cos(8t)*sin(t) + 13sin(8t)*cos(t)]dt

A = (1/2)*integral(13sin(8t)*cos(t)*[104cos(8t)*sin(t) + 13sin(8t)*cos(t)]dt - 13sin(8t)*sin(t)*[104cos(8t)*cos(t) - 13sin(8t)*sin(t)]dt)

I'm not sure how go about evaluating this integral.