Question

Suppose f(x)=x^2 what is the graph of g(x)=f(2x)

i have seen other descriptions saying that you should substitute 2x into the equation, but where does that 2x come from and what is next?

Answer 1

Since g(x) = f(2x), this means we substitute 2x in place of x for f(x):

g(x) = f(2x) = (2x)² = 4x²

Graphing this, the parabola is not moved from the parent graph f(x) = x², but the graph is compressed horizontally by a factor of 4.Explanation: