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Thread: Can't figure out this log problem

  1. #1

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    Can't figure out this log problem

    The answer is 16 but I can only get 8 when I solve it

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  2. #2
    Fanatic Member alkatran's Avatar
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    10^(x*y) = (10^x)^y
    so:
    10^(log10(2) * 4) = (10^log10(2))^4

    x^logx(y) = y
    so:
    (10^log10(2))^4 = 2^4 = 16
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  3. #3

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    thanks, I kept running in the loop of multiplying the 4*2=8
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  4. #4
    vbuggy krtxmrtz's Avatar
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    A similar approach based on the fact that

    log(xy) = y * log(x)

    4 log10(2) = log10(24) = log10(16)

    and by definition, 10log(something) = something
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