Please Help! I tried doing this on my own and got the wrong answer.

Differentiate:
y=4/(x-x^2)^(1/4)

write it as

y = 4(x-x^2)^(-1/4)

dy/dx = -1(x-x^2)^(-5/4) (1 - 2x)

= (2x-1)/(x - x^2)^(5/4)