# How do I find the derivative of the function f(x) = 9x^2 ln(8x)?

$f ' \left(x\right) = 18 x \ln \left(8 x\right) + 9 x$
$f ' \left(x\right) = 18 x \ln \left(8 x\right) + 9 {x}^{2} \cdot 1 \left(8 x\right) \cdot 8$
$f ' \left(x\right) = 18 x \ln \left(8 x\right) + 9 x = 9 x \left(2 \ln \left(8 x\right) + 1\right)$