### Theory:

Modulus or Absolute valued Function:
A function $$f: \mathbb{R} \rightarrow [0, \infty)$$ defined by $$f(x) = |x|$$.
Where $$f(x) = \begin{cases} x & , x\geq 0 \\ -x & , x<0 \end{cases}$$
The graphical representation of modulus or absolute valued function is given by:

Cubic Function:
A function $$f: \mathbb{R} \rightarrow \mathbb{R}$$ defined by $$f(x) = ax^3 + bx^2 + cx + a$$, $$(a \neq 0)$$ is called a cubic function.
$$f(x) = x^3$$ is an example of cubic function.

This function is graphically represented as follows: