Question:
Let $f, g: \mathbf{R} \rightarrow \mathbf{R}$ be defined by $f(x)=2 x+\mid$ and $g(x)=x^{2}-2$ for all $x \in \mathbf{R}$, respectively. Then, find gof.
[NCERT EXEMPLAR]
Solution:
We have,
$f, g: \mathbf{R} \rightarrow \mathbf{R}$ are defined by $f(x)=2 x+\mid$ and $g(x)=x^{2}-2$ for all $x \in \mathbf{R}$, respectively
Now,
$g o f(x)=g(f(x))$
$=g(2 x+1)$
$=(2 x+1)^{2}-2$
$=4 x^{2}+4 x+1-2$
$=4 x^{2}+4 x-1$