From GeoGebra Manual
- Function[Function f, Number a, Number b]
- Yields a function that is identical to the original function f, but whose graph is restricted to the interval [a, b].
- This command should be used only to restrict the display interval of a function. To restrict the function’s domain, create a conditional function with the If Command.
- Example: f(x) = Function[x^2, -1, 1] produces a function equal to x2 whose graph appears only in the interval [-1, 1]. However, while g(x) = 2 f(x) will produce the function g(x) = 2 x2, this function is not restricted to the interval [-1, 1].