# Function Command

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*].

**Note:**

- 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*x*whose graph appears only in the interval [^{2}*-1*,*1*]. However, while`g(x) = 2 f(x)`will produce the function*g(x) = 2 x*, this function is not restricted to the interval [^{2}*-1*,*1*].