• May 20th 2008, 07:16 PM
jscalalamoboy
k... so...

How do you simplify these when they are in fraction form.

All help greatly appriciated!

[JSC]AL(AL)AMOBOY
• May 20th 2008, 09:17 PM
Mathstud28
Quote:

Originally Posted by jscalalamoboy
k... so...

How do you simplify these when they are in fraction form.

All help greatly appriciated!

[JSC]AL(AL)AMOBOY

$\frac{\sqrt{a}}{\sqrt{b}}=\frac{\sqrt{ab}}{{b}}$

$\frac{\sqrt{a}}{b}$ no need for simplification

$\frac{a}{\sqrt{b}}=\frac{a\sqrt{b}}{b}$

In upper math you (or from what I have seen) rarely do this
• May 21st 2008, 01:37 AM
Moo
Hello,

Quote:

Originally Posted by Mathstud28
$\frac{\sqrt{a}}{\sqrt{b}}=\frac{\sqrt{ab}}{{b}}$

Be careful for this one :D

If you have $\sqrt{ab}$, it isn't necessarily equal to $\sqrt{a} \sqrt{b}$.

Because a and b can be both negative.

$\sqrt{ab}$ will be defined, but not $\sqrt{a}\sqrt{b}$

For example, let's take a=-2 and b=-3.

$\sqrt{ab}=\sqrt{(-2)(-3)}=\sqrt{6}$

But $\sqrt{a} \sqrt{b}=\sqrt{-2} \sqrt{-3}$

Which is... weird :D