Question

Find f(5x) .The function f is defined by f(x) = 2x ^ 2 - 4 .

Answer 1

Given:

`f(x)=2x^2-4`

To find f(5x), this means the value of f(x) when x = 5x

Hence,

`\begin{gathered} f(x)=2x^2-4 \\ f(5x)=2(5x)^2-4 \\ f(5x)=2(25x^2)-4 \\ f(5x)=50x^2-4 \end{gathered}`

Therefore,

`f(5x)=50x^(2)-4`