# How do you find domain and range for # f(x) = (x^2) - 2x - 15#?

##### 1 Answer

Oct 2, 2015

This is an equation of a parabola that opens upward and will have a minimum value for y at the vertex.

#### Explanation:

Since this is a parabola opening upward, the domain is all real values for x:

The general formula for a parabola is:

Now, find the vertex using this formula for the x-coordinate:

Finally, we can find the lower limit for y by inserting the x-coordinate of the vertex into the original equation:

So, the range is

Here is a graph of the parabola:

hope that helped