Find the Derivative of the Function Using the Definition of Derivative

Multiple Choice

Find the derivative of the function using the definition of derivative.
- $$f ( x ) = 3 x ^ { 2 } - 4 x$$

A) $f ^ { \prime } ( x ) = 2 x - 4$
B) $f ^ { \prime } ( x ) = 6 x - 4$
C) $f ^ { \prime } ( x ) = 3 x - 4$
D) $f ^ { \prime } ( x ) = 6 x$