Question

In the problem below, $f\left(x\right)=x^2$ and $g\left(x\right)=4x-2$
Find the following function: $(f\circ g)\left(x\right)$

• A. $8x^2-12x+4$
• B. $16x^2-16x+4$
• C. $8x^2-14x+6$
• D. $12x^2+10x-2$

Answer 1

Answer: (B)

$16x^2-16x+4$

Given, $f\left(x\right)=x^2$ and $g\left(x\right)=4x-2$
$\Rightarrow \left(fog\right)\left(x\right)=f\left(g\right(x\left)\right)$

$=f(4x-2)$

$={(4x-2)}^2$

$=16x^2-16x+4$