20: The domain is D( f ) = ℝ.
The derivative is

Critical points: The equation f ′(x) = 0 has solution x = 1.
The derivative does not exist at x = 0 and x = 2.

Intervals of monotonicity will be (−∞,0], [0,1], [1,2], and [2,∞). Determine monotonicity and local extrema using a chart.

Next hint
Answer