Question 3 Use Green's theorem to evaluate the line integral

C(2y+9+x3))dx+(5x+earctany)dy

where C is the positively oriented circle ²+²=4

Question 3 Use Green's theorem to evaluate the line integral jg (2y + 1/9 + x3) dx + (5x + ercmnymy. C where C is the positively oriented circle 1:2 + y2 = 4i Question 4 Suppose that C is a positively oriented piecewise-smooth simple closed curve that encloses the origin (0. 0). Show that -ydx + xdy = 21 x2 + y2 and also show that this integral is zero if C does not enclose the origin.