Question

If $f\left(x\right)=x^2$, find $\frac{f\left(4\right)-f\left(2\right)}{(4-2)}$

Answer 1

$\to f\left(x\right)=x^2$

$\therefore f\left(4\right)=4^2=16$

$\therefore f\left(2\right)=2^2=4$

$\therefore \frac{f\left(4\right)-f\left(2\right)}{4-2}=\frac{16-4}{4-2}$

$\therefore \frac{f\left(4\right)-f\left(2\right)}{2}=\frac{12}{2}=6$