Question

Given the function f(×)=3×2-5 then f(4) is equal to?

Answer 1

Given,

$\[f\left( x \right) = 3{x^2} - 5\]$

Solution,

Calculate the value of $\[f\left( 4 \right)\]$.

Put $\[x = 4\]$

$\[\begin{array}{l}f\left( 4 \right) = 3 \times {\left( 4 \right)^2} - 5\\ \Rightarrow f\left( 4 \right) = 3 \times 16 - 5\\ \Rightarrow f\left( 4 \right) = 48 - 5\\ \Rightarrow f\left( 4 \right) = 43\end{array}\]$

Hence the value of $\[f\left( 4 \right)\]$ is $\[43\]$