I constructed my own question to try to make sense of the following notation.
g(x) = 2√x g : X → Y. What does X and Y equal?
For 2√x, x = or > than 0.
The Attempt at a Solution
g(x) = 2√x g : [0, ∞) → [0, ∞)
So X = Y = [0, ∞)
The reason why I am doing this is because my book shows this: g(x) = 2√x g : [1,∞) → [2,∞). Why does my book have a 1 instead of a 0 as an initial x value?