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rationalising surds

How would you go about rationalising something where the denominator is all in brackets like:

(2 + √3)^2
Original post by preludefaun
How would you go about rationalising something where the denominator is all in brackets like:

(2 + √3)^2


post the full question please


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Original post by preludefaun
How would you go about rationalising something where the denominator is all in brackets like:

(2 + √3)^2


I don't see a denominator there. 0.o

Could you simply FOIL out the 2​?
Original post by anosmianAcrimony
I don't see a denominator there. 0.o

Could you simply FOIL out the 2​?


he is saying that is the denominator


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Reply 4
The full question is to rationalise:

3√2 - 2√3 / (√2 + √3)^2
Original post by preludefaun
How would you go about rationalising something where the denominator is all in brackets like:

(2 + √3)^2


expand that out and u will an answer in the form a+broot(3) and then carry on as u normally would by multiplying top and bottom by a-broot(3). find a and b by urself


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Reply 6
Yeah I think I'm just going to expand the denominator out then rationalise.
Original post by physicsmaths
he is saying that is the denominator


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Oh, I see.
ignore my previous post as i read it wrong. expand root 2 + root 3 squared and see whatu get. u shud get something in the form a+broot(6). after that rationalise normally


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Original post by preludefaun
Yeah I think I'm just going to expand the denominator out then rationalise.


That should do it. Good luck.

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