Verified answer

this is the complete answer! enjoy your studies in math! :))

Guys I think when she said use the *definition of derivatives*, she meant

f'(x) = lim_{Δh -> 0 } { [f(x + Δh) - f(x)]/Δh }

Not directly use chain rule, etc. I am not going to do it, but it seems like people are interpreting this wrong?

this is a chain rule problem -2sin^5(x)

or -2 (sin x)^5

-2*cos*5 (sin x)^4

-10 cos x(sin x)^4