Posted by **-Untamed-** on Monday, October 3, 2011 at 9:40pm.

About rationalizing denominator, is it true that you can't always multiply by the same square root denominator to get a perfect square?

- Calculus -
**Steve**, Tuesday, October 4, 2011 at 8:56am
yes, because (√n)² = n

so, multiplying the root by itself gets rid of the root.

If the denominator is not just a root, but something like √m + n, then you need to multiply by √m - n, since

(√m + n)(√m - n) = m - n²

also, you sometimes have to use

(√m + √n)(√m - √n) = m - n

## Answer This Question

## Related Questions

- Algebra - Rationalize each expression by building perfect nth root factors for ...
- College Algebra - I need some help with a handful of questions. I need to see ...
- College Algebra - I need some help with a handful of questions. I need to see ...
- Math help plz ASAP. - Rationalize each denominator. 6 + square root of 2 ...
- College Algebra help please - I need some help with a handful of questions. I ...
- Algebra - I need to rationalize the denominator of 2/3 square root of five, (...
- math - Simplify the radical expression by rationalizing the denominator: 2(...
- math - Simplify th radical expression by rationalizing the denominator: 2(square...
- Some Please Help me - PreCalc - Verify that the point ( square root(31)/7, -...
- Algebra 2 - simplify the radical expression by rationalizing the denominator. 4...

More Related Questions