9. (20 分) Using Green's Theorem, evaluate clockwise around the boundary curve C of the region R = {(x, y) R | 1≤ y≤2 - x2}, where F= (x2 + y2)i + (x2 - y2)j. (10 分) (請說明 Green's theorem 之公式 (5 分)、畫出 R 之圖形 (5 分))