In general, the square root of a number can be either positive or negative. Determining domain word problem (positive integers) Webthe sequence of graphs in figure 2 also help us identify the domain and range of the square root function.

Note that it includes 0 as well in the domain. Determining domain word problem (real numbers) worked example: I. e. , √25 = 5. In figure 2 (a), the parabola opens outward indefinitely, both left. I. e. , the square root function domain is [0, ∞).

I. e. , the square root function domain is [0, ∞).