Answer
Increasing: (-∞,0) and (2,67, ∞)
Decreasing: (0, 2.67)
Work Step by Step
$f(x) = x^3 - 4x^2$
From the graph attached below, the function is increasing from (-∞,0) and (2,67, ∞)
(2.67 is determined by eye, but it can also be determined by taking the derivative (which is calculus: $3x^2 - 8x$) and setting it equal to 0, which leads to an answer of 8/3)
It is decreasing between (0, 2.67)
