Let . On which interval is the graph of concave…

MATHEMATICS · Single correct · AP · Calculus AB · Analytical Applications of Differentiation · Analytical Applications of Differentiation

Problem

Let

f(x)=x^{4}-4x^{3}

. On which interval is the graph of

f

concave downward? (a)

(-\sqrt{2},\sqrt{2})

(b)

(0,2)

(c)

(-\infty,3)

(d)

(-\infty,0)\cup(2,\infty)