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# A-Level surds maths question - really need help on how to do this please

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1. Show that 1/(1+(1/√2)) can be written as 2-√2
2. (Original post by fionachristie)
Show that 1/(1+(1/√2)) can be written as 2-√2
What have you tried so far?
3. 1/√2 x √2/√2 = √2/2 and then I don't know where to go from here because I would cancel out the 1's and be left with an answer of √2/2 but that's clearly wrong if it tells me the answer is 2-√2
4. (Original post by fionachristie)
1/√2 x √2/√2 = √2/2 and then I don't know where to go from here because I would cancel out the 1's and be left with an answer of √2/2 but that's clearly wrong if it tells me the answer is 2-√2
Okay so you have , now multiply top and bottom by to get now rationalise this by your usual method.

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Updated: September 9, 2016
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