Let $f ( x ) = x ^ { 3 } - 9 x ^ { 2 } + 15 x$

Multiple Choice

Let $f ( x ) = x ^ { 3 } - 9 x ^ { 2 } + 15 x$ Then ƒ has a relative minimum at x =

A) 0
B) 1
C) 2
D) 4
E) 5