How do you find the domain and range of f(x)=2x21?

1 Answer
Aug 20, 2017

See below.

Explanation:

The value under a radical cannot be negative, or else the solutions will be complex.

So,

2x210

2x21

x212

x22 and x22. In interval notation, this is (,22][22,)

Since the radical value will always be greater than or equal to zero, the range is just [0,).