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C1 Simple maths: can you guys just check a few of these? watch

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    (Original post by RMorley)
    It is but he has written it in an odd manner

    he means \frac{2\sqrt 3}{3}
    Oh, right yeah. I read it as \frac{1}{3(2\sqrt3)}. Apologies.
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    (Original post by RMorley)
    25/3 is correct.

    If you think about it if a^{p}=5

    then squaring both sides means

    a^{2p}=25

    Can you work out the a^{-0.5q}

    Spoiler:
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    a^{-0.5q}=1/3
    Ok so

    a^{2p}=25

    but for a^{-0.5q}

    Could've of sworn it was 3, not 1/3 - oh man this is hard to get my head around...
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    (Original post by Dededex)
    Ok so

    a^{2p}=25

    but for a^{-0.5q}

    Could've of sworn it was 3, not 1/3 - oh man this is hard to get my head around...
    Don't worry you are nearly there.

    a^{q}=9

    therefore a^{-q}=1/9

    (anything to the power of -1 is one over that i.e. 2^-1 is a half)

    If you root both sides

    a^{-0.5q} =1/3
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    (Original post by RMorley)
    25/3 is correct.

    If you think about it if a^{p}=5

    then squaring both sides means

    a^{2p}=25

    Can you work out the a^{-0.5q}

    Spoiler:
    Show
    a^{-0.5q}=1/3
    Because wouldn't you be square rooting both sides since it's to power half - so it'd be 3? not one third?
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    First one is 25/3.
    a^-0.5 = 1/a^0.5
    a^0.5 = square root of a
    got it?
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    (Original post by rofflewaffle)
    That isn't correct. How did you get that?
    it is correct just wrote it in a different form(like rmorley mentioned)
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    (Original post by RMorley)
    Don't worry you are nearly there.

    a^{q}=9

    therefore a^{-q}=1/9

    (anything to the power of -1 is one over that i.e. 2^-1 is a half)

    If you root both sides

    a^{-0.5q} =1/3
    Oh FFS I understand now, so sorry mate - should've known that -_- such a noob.

    So when you get third and 25, how come you divide them in the end?
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    (Original post by Dededex)
    Because wouldn't you be square rooting both sides since it's to power half - so it'd be 3? not one third?
    Yes but you are forgetting the minus power

    you have a^{0.5q} =3 which is correct

    but you need to work out

    a^{-0.5q} which is where the 1/3 comes from
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    (Original post by Dededex)
    Oh FFS I understand now, so sorry mate - should've known that -_- such a noob.

    So when you get third and 25, how come you divide them in the end?
    (5)^2/root9=25/3 you get it now?
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    (Original post by Dededex)
    Oh FFS I understand now, so sorry mate - should've known that -_- such a noob.

    So when you get third and 25, how come you divide them in the end?
    You times them as

    a^{b+c}

    = a^{b} a^{c}

    Therefore

    a^{2p-0.5q}=

    a^{2p}a^{-0.5q}

    So substituting your values it is 25 times by 1/3 i.e. 25/3
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    (Original post by Remarqable M)
    it is correct just wrote it in a different form(like rmorley mentioned)
    I know, I read it wrong (see above). Sorry .
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    (Original post by RMorley)
    You times them as

    a^{b+c}

    = a^{b} a^{c}

    Therefore

    a^{2p-0.5q}=

    a^{2p}a^{-0.5q}

    So substituting your values it is 25 times by 1/3 i.e. 25/3
    Aah yeah I see, thanks for all your help now - have to admit, I thought I was cool on indices but that MoFo was tight :P
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    (Original post by RMorley)
    You times them as

    a^{b+c}

    = a^{b} a^{c}

    Therefore

    a^{2p-0.5q}=

    a^{2p}a^{-0.5q}


    So substituting your values it is 25 times by 1/3 i.e. 25/3

    wait isn't better to separete them first ? like a^2p/a^1/2q >> then (a^p)^2/(a^q)^0.5
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    (Original post by Dededex)
    Aah yeah I see, thanks for all your help now - have to admit, I thought I was cool on indices but that MoFo was tight :P
    Quite alright, they take a while to get used to and you just have to practice to be confident with them
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    (Original post by rofflewaffle)
    I know, I read it wrong (see above). Sorry .
    :lol: ok
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    (Original post by RMorley)
    You times them as

    a^{b+c}

    = a^{b} a^{c}

    Therefore

    a^{2p-0.5q}=

    a^{2p}a^{-0.5q}

    So substituting your values it is 25 times by 1/3 i.e. 25/3
    One more thing though - surely when you multiply two powers together you add them? Not 25 times 1/3 but 25 + 1/3? Hmm that bit is just a little weird.
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    (Original post by Dededex)
    One more thing though - surely when you multiply two powers together you add them? Not 25 times 1/3 but 25 + 1/3? Hmm that bit is just a little weird.
    You do, but here they were adding, but you spilt them up so they were multiplying. Think of it this way if you know x=3 and you need to work out x^2

    you can express X^2 and x^1 multiplied by x^1 so it is 3x3=9 rather then 3+3
 
 
 
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