Find the Interval(s) Where F Is Concave Up For $f ( x ) = 4 x ^ { 4 } - 3 x ^ { 3 } + 5 x - 10$

Multiple Choice

Find the interval(s) where f is concave up for $f ( x ) = 4 x ^ { 4 } - 3 x ^ { 3 } + 5 x - 10$

A) (-?, ?)
B) (-?, 0) ? $\left( \frac { 3 } { 8 } , \infty \right)$
C) $\left( \frac { 3 } { 8 } , \infty \right)$
D) $\left( - \infty , \frac { 3 } { 8 } \right)$
E) $(\left. 0 , \frac { 3 } { 8 } \right)$