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    This isn't an academic-related question, it's purely a maths challenge question to be tried if you wish.

    Can anybody make 37 using only the number 4 with a limit of four times to use it?

    Things you can do with the fours include use parenthesis (brackets), add, multiply, divide, subtact, use four factorial, use square root of four and use four after a decimal point e.g. 0.4, 4.4, 44.44.

    Good luck. Btw try to do it without searchign for the answer on the internet.
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    (Original post by UnbeatableZoomy)
    This isn't an academic-related question, it's purely a maths challenge question to be tried if you wish.

    Can anybody make 37 using only the number 4 with a limit of four times to use
    Spoiler:
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    4! + (4! + root4)/root4

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    Ha. Now show that if we allow logs into the game only three fours are necessary to represent any positive integer.
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    (Original post by Lord of the Flies)
    Ha. Now show that if we allow logs into the game only three fours are necessary to represent any positive integer.
    I did not even like the idea of a decimal place

    Logs is going too far

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    (Original post by Lord of the Flies)
    Ha. Now show that if we allow logs into the game only three fours are necessary to represent any positive integer.
    You can though it would be impossible to make any positive integer.
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    (Original post by UnbeatableZoomy)
    You can though it would be impossible to make any positive integer.
    Not sure what you're saying, if you allow logs you can get any positive integer using only three fours (and it is possible to construct a general expression, which is what I was asking for).
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    (Original post by Lord of the Flies)
    Not sure what you're saying, if you allow logs you can get any positive integer using only three fours (and it is possible to construct a general expression, which is what I was asking for).
    Does it have to be to base 4 or some operation of 4 or can we use the natural logarithm?
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    (Original post by Felix Felicis)
    Does it have to be to base 4 or some operation of 4 or can we use the natural logarithm?
    Natural.
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    (Original post by Lord of the Flies)
    Natural.
    Hmm...
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    (Original post by Lord of the Flies)
    Natural.
    Goddammit, this took ages

    Spoiler:
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    For a positive integer, n, n = \dfrac{\ln \left( \ln 4/ \ln \underbrace{\sqrt{\sqrt{\sqrt{ \cdots \sqrt{4}}}}}_{2n}\right)}{\ln 4}
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    (Original post by Felix Felicis)
    Goddammit, this took ages

    Spoiler:
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    For a positive integer, n, n = \dfrac{-ln[ln( \displaystyle\underbrace{ \sqrt{\sqrt{\sqrt{...\sqrt{4})}}  }}_{2n} /ln4]}{ln4}
    :lolwut:
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    (Original post by Sketch)
    :lolwut:
    I execrate problems like these but never turn down a challenge
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    (Original post by Felix Felicis)
    Goddammit, this took ages

    Spoiler:
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    n = \dfrac{\ln\left(\ln 4/\ln \displaystyle\underbrace{ \sqrt{\sqrt{\sqrt{...\sqrt{4}}}}  }_{2n}\right)}{\ln 4}
    Precisely
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    (Original post by Lord of the Flies)
    Precisely
    Argh, how do you make the latex so neat Mine was hideous
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    (Original post by TenOfThem)
    that is the answer i gave in post 2
    Yeah I didn't check what your answer was before I posted, now I have so I deleted my comment
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    I don't want to look at the answers, but can we use any powers of 4, 4^0 or 4^1.5 etc. ?
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    (Original post by andypandy11)
    I don't want to look at the answers, but can we use any powers of 4, 4^0 or 4^1.5 etc. ?
    No
 
 
 
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