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    • Thread Starter
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    Hi

    Can anyone help with the following:

    (2+√2)(3+√5)(√5-2)
    (√5-1)(1+√2)

    I have managed to get to the following but not sure what to do from here:

    2√5 – 2 + √10 + √50 - 6√2
    √5 + √10 - 1 - √2

    Thanks
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    Welcome Squad
    (Original post by Flutegirl02)
    Hi

    Can anyone help with the following:

    (2+√2)(3+√5)(√5-2)
    (√5-1)(1+√2)

    I have managed to get to the following but not sure what to do from here:

    2√5 – 2 + √10 + √50 - 6√2
    √5 + √10 - 1 - √2

    Thanks
    What is your objective? If it's to rationalise the denominator then just multiply your fraction by \displaystyle \frac{(\sqrt5+1)(1-\sqrt2)}{(\sqrt5+1)(1-\sqrt2)} before you expand the brackets.
    • Thread Starter
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    Thanks. Yeah it's rationalising. I'll have a go tomorrow.
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    The trick is to keep the denominator factorised, at least until you have done the 'multiply top and bottom by this' trick.
 
 
 
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