$f(x) = \left(\frac{x+2}{x-1}\right)^3$ fonksiyonunun türevi olan $f'(x)$ aşağıdakilerden hangisidir?
A) $\frac{-9(x+2)^2}{(x-1)^4}$
B) $\frac{-3(x+2)^2}{(x-1)^4}$
C) $\frac{9(x+2)^2}{(x-1)^4}$
D) $\frac{3(x+2)^2}{(x-1)^3}$
E) $\frac{-9(x+2)^3}{(x-1)^4}$
