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    Ok, so I was doing a past paper and really panicked when I came across this question. I'm probably being silly but I always have trouble when having to root numbers (that are higher than square roots, and 3rd roots).

    e.g. fifth root of 32 (taken from part 'a' the following question)...
    Name:  C1 June 2012 Q2(a) root numbers.png
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    Can someone link a video or explain to me the procedure of rooting numbers please?
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    (Original post by Philip-flop)
    Ok, so I was doing a past paper and really panicked when I came across this question. I'm probably being silly but I always have trouble when having to root numbers (that are higher than square roots, and 3rd roots).

    e.g. fifth root of 32 (taken from the following question)...
    Name:  C1 June 2012 Q2(a) root numbers.png
Views: 97
Size:  5.1 KB
    I'm not sure if they'd ever give you a disgusting number to work with. Eg fifth root of 234.

    So perhaps it's worth checking numbers like 2,3,4 etc. After all, you know that 32^0.6 is going to be less than 32^1 so the 5fth root can't be that big.
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    You're expected to know 2 to any index. 32 is 2^32. I haven't seen them use powers higher than three for any other number, but if they do, try to figure it out.
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    (Original post by Jasaron)
    You're expected to know 2 to any index. 32 is 2^32. I haven't seen them use powers higher than three for any other number, but if they do, try to figure it out.
    32 is not 2^32.
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    (Original post by Philip-flop)
    Ok, so I was doing a past paper and really panicked when I came across this question. I'm probably being silly but I always have trouble when having to root numbers (that are higher than square roots, and 3rd roots).

    Can someone link a video or explain to me the procedure of rooting numbers please?
    At this level, you'll need to realise that "rooting" numbers in the exam means looking for a way to represent the given number in a different format such that the rooting process becomes easy.

    So, you'll see 32^{1/5} and you should be thinking "what ways can I represent 32 as a number to the power 5 (or to the power 10 or to the power 15, etc... so that the power cancels the root nicely". In this case, it's particularly easy because there aren't many possible numbers. 3^5 is far bigger than 32, 2^10 is far bigger than 32, so the only possible thing is 2^5, really.

    Then: (2^5)^{1/5} = 2^{5/5} = 2.
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    (Original post by Zacken)
    At this level, you'll need to realise that "rooting" numbers in the exam means looking for a way to represent the given number in a different format such that the rooting process becomes easy.

    So, you'll see 32^{1/5} and you should be thinking "what ways can I represent 32 as a number to the power 5 (or to the power 10 or to the power 15, etc... so that the power cancels the root nicely". In this case, it's particularly easy because there aren't many possible numbers. 3^5 is far bigger than 32, 2^10 is far bigger than 32, so the only possible thing is 2^5, really.

    Then: (2^5)^{1/5} = 2^{5/5} = 2.
    Wow, thanks Zacken!! You giving me a different perspective/ way of looking at it has made this so much clearer in how to tackle these kind of problems
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    (Original post by Zacken)
    32 is not 2^32.
    Give me a second... I'm just going to drop AS maths. :banghead:

    32 is 2^5*
 
 
 
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