Find the derivative of the function f ( x ) = ( x^2 - x )^2 .

4 x^3 - 6 x^2 + 2 x

2( x^2 + 2 x )

4 x^3 - 12 x + 8 x

2 x - 2

from the chain rule,

f' = 2(x^2-x)(2x-1)
so, which choice is that?