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    Hey,

    I know the rules for surds, however I still don't get them.

    For example-/20 =-/ 4×5 which then equals 2-/5 (this " -/" is the surd sigh seen as I don't have one my phone haha. And the example is out of my so called " revision guide")

    If someone could explain this process then thank you.
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    _/ab = _/a * _/b

    Do you understand this rule?
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    root(ab) = root(a)root(b)

    if a or b is a square number, the function root(a) or root(b) will output an integer. if the output of root b is not an integer and the output of root a is an integer, it can be written as xroot(b) where x is the root of a.
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    Yeah I understand that rule, just not how they get a number in front of the surd

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    Urm I kinda get that now thank you.

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    (Original post by jade2000)
    Yeah I understand that rule, just not how they get a number in front of the surd

    Posted from TSR Mobile
    root(20)=root(4x5)...
    however, root(4x5)=root((2^2)x5)
    as 4 is a square number (2^2) it can be rooted so
    root(4x5)=root(4) x root(5)
    =2root(5)

    Hope this makes sense...
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    (Original post by Nirvana27)
    root(20)=root(4x5)...
    however, root(4x5)=root((2^2)x5)
    as 4 is a square number (2^2) it can be rooted so
    root(4x5)=root(4) x root(5)
    =2root(5)

    Hope this makes sense...
    Oh right yes that makes sense, thank you
 
 
 
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Updated: October 29, 2015
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