Strategy:
1. Sketch parabola translated 1 unit down (x^2 1)
2. Absolute function returns positive values only.
Reflect negative part of the curve on xaxis
to get the Sketch of f(x)
3. Derivative at Cusp/Corner is not defined.
Therefore, define function as a piecewise function in 5 parts
dividing the domain at xintercepts.
4. Sketch the derivative with table of values.