I need to eliminate the imaginary numbers from the denominator of the following equation and I have no idea where to start.

3/(s+2-2i)

Please help!

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- Aug 31st 2006, 05:32 AMafn2Eliminating Imaginary Numbers from a Denominator
I need to eliminate the imaginary numbers from the denominator of the following equation and I have no idea where to start.

3/(s+2-2i)

Please help! - Aug 31st 2006, 06:35 AMThePerfectHackerQuote:

Originally Posted by**afn2**

*conjuage*

$\displaystyle \frac{3}{(s+2)-2i} \cdot \frac{(s+2)+2i}{(s+2)+2i}$

Thus,

$\displaystyle \frac{3(s+2)+3(2i)}{(s+2)^2-4i^2}$

Thus,

$\displaystyle \frac{3s+6+6i}{s^2+4s+8}$ - Aug 31st 2006, 06:41 AMtopsquarkQuote:

Originally Posted by**afn2**

$\displaystyle \frac{3}{2+\sqrt{5}}$

and

$\displaystyle \frac{3}{2+i} = \frac{3}{2+\sqrt{-1}}$

In each case the denominator takes the form $\displaystyle a+\sqrt{b}$ and you need to multiply the denominator by $\displaystyle a-\sqrt{b}$ to remove the square root.

-Dan - Aug 31st 2006, 07:48 AMafn2
THANKS a MILLION for the help guys. I had been reading help hints on the internet all day, but wasn't really getting what they were trying to say, so this really helped!