Question

Let $f\left(x\right)=x^2-1,xϵR$. Find $\frac{1}{2}f\left(5\right)$

Answer 1

Given, $f\left(x\right)=x^2-1$

Therefore, $\frac{1}{2}f\left(5\right)=\frac{1}{2}\times (5^2-1)$

$=\frac{1}{2}\times \left(25-1\right)$

$=\frac{24}{2}$

$=12$