Question

The function f is defined by f(x) = 2x²-1. Find f (2x).

Answer 1

Answer: $f(2x)=8x^2-1$

Step-by-step explanation:

All that is required here is to substitute x = 2x into the right side in the same way that is done for a numeric value.

$f(2x) = 2(2x)^2-1\\f(2x) = 2(4)x^2-1\\f(2x) = 8x^2-1$