Radical function

Question

Answer the following questions:

1) How do we find the domain of a radical function? Provide an example.

2) What does "rationalizing the denominator" mean?

Answer 1

2)  rationalizing the denominator means performing an operation on a ratio such that its overall value is unchanged but the denominator no longer contains any irrational.

 

1) the domain of a square root, or any even-index radical, is obtained by setting the radical ≥ 0 and solving that inequality.  (If the radical is the denominator, set it > 0).   Example: f(x) = √(6-4x) requires 6-4x ≥ 0, or 6 ≥ 4x, or x ≤ 3/2.