The function B(a, B) is defined by ya-1(1 - y) 8-1dy. (a) Letting y = sin 0, show that B(a, B) = 2 So Cat /2 sin24-1 cos28-1 de. (b) Write I(a)I (B) as a double integral, transform to polar coordinates, and conclude that T(a)r (B) B(a, B) = (a + B)