Question

(sin^2y)/(1-cosy)

Answer 1

(sin^2y)/(1-cosy)

multiplying times 1+cos(y) on top and bottom,

(sin^2y+cos(y)sin^2y ) / (1-cos^2(y))

(sin^2y+cos(y)sin^2y ) / (sin^2(y))

1+cos(y).