# What is the domain and range of f(x)= 4?

Aug 16, 2015

Domain: $\left(- \infty , + \infty\right)$
Range: $\left\{4\right\}$

#### Explanation:

You're dealing with a constant function for which the output, i.e. the value of the function, is always constant regardless of the input, i.e. the value of $x$.

In your case, the function is defined for any value of $x \in \mathbb{R}$, so its domain will be $\left(- \infty , + \infty\right)$.

Furthermore, for any value of $x \in \mathbb{R}$, the function is always equal to $4$. This means that the range of the function will be that one value, $\left\{4\right\}$.

graph{y - 4 = 0.001 * x [-15.85, 16.19, -4.43, 11.58]}