i need to rationalise the denominators of this $\displaystyle \frac{1}{\sqrt{3}} $

can someone explain what i need to do?

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- Jan 15th 2010, 08:18 AMandyboy179rationalise
i need to rationalise the denominators of this $\displaystyle \frac{1}{\sqrt{3}} $

can someone explain what i need to do? - Jan 15th 2010, 09:08 AMArchie Meade
Multiply by $\displaystyle \frac{\sqrt{3}}{\sqrt{3}}$ to change the denominator to an integer.

- Jan 15th 2010, 09:19 AMandyboy179

i was gonna post because i thought it was that, so the answer would be Attachment 14832

- Jan 15th 2010, 09:23 AMVonNemo19
yes, but do you need the 1?

- Jan 15th 2010, 09:26 AMArchie Meade
Yes, that's it,

beyond that,

you would use the "surd conjugate" when the denominator is

composed of an integer and square root....

example

$\displaystyle \frac{1}{2+\sqrt{3}}=\frac{1}{2+\sqrt{3}}\ \frac{2-\sqrt{3}}{2-\sqrt{3}}$ - Jan 15th 2010, 10:16 AMandyboy179
- Jan 15th 2010, 07:57 PMdifferentiate
understand that rationalise the denominator means to change the denominator so that it is a rational number (i.e. no surds!)

some people rote learn maths and decide to multiply top and bottom by the denominator, which is obviously not the case, as sometimes you need to multiply by the surd conjugate.

so yeah