# What are the extrema of f(x) = 3x^2 + 12x + 16?

Nov 10, 2015

$x = - 2$ is a minimum.
$f ' \left(x\right) = 6 x + 12 = 0$
$x = - 2$
$f ' ' \left(- 2\right) = 6 > 0$ $\implies$ local minimum