f(x)=(x^2 -2x)(3x-1) is a product and is most easily differentiated using the product rule:
f '(x) = (x^2 - 2x)(3) + (3x-1)(2x-2)
Now subst. 2 for x in this equation. We get:
f '(2) = (2^2 - 2(2))*3 + (3(2)-1)(2(2) -2), or
=3(4-4) + (6-1)(2) so f '(2) = 10 (answer)
