Evaluate rab-b'x? - a?y? jva bby?a?a dx dy, over the positive quadrant of the ellipse x/a2 + y2/b2 1. to evaluate ab +b°x +a'y = 1, by putting x = au dx = a du,

evaluate rab-b'x? - a?y? JVa bby?a?a dx dy, over the positive quadrant of the ellipse x/a2 + y2/b2 1. To evaluate ab +b°x +a'y = 1, by putting x = au dx = a du, and y = bv dy = bdv, we have to evaluate ab - du - v? -uf + dv, over the positive quadrant of the circle už + V = 1.