Question

If `f(x)=2x^2`, how do you find `f(2x)`?

Answer 1

Substitute in the `2x` for every `x` in the function to get to `f(2x)=8x^2`

Explanation:

When we have a question that gives a function, such as `f(x)=2x^2` and we are then asked what that function would then be with `f(2x)`, we substitute the `2x` in for every `x` we see. Like this:

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

We can now simplify it:

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

`f(2x)=8x^2`