The Function $f ( x ) = \frac { 1 } { 3 } x ^ { 3 } - 25 x$

Multiple Choice

The function $f ( x ) = \frac { 1 } { 3 } x ^ { 3 } - 25 x$ satisfies the hypotheses of Rolle's Theorem on the interval $[ 0,5 \sqrt { 3 } ]$ . Find all values of $c$ that satisfy the conclusion of the theorem.

A) $\pm 5$
B) 5
C) $\pm 4$
D) 4