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    How would I go about solving this problem:
    5000x = 2^(x-1)

    Thanks
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    5000x = 2^(x-1)
    5000x = (x-1)(x-1)
    5000x = x^2 - x - x + 1 = 0
    x^2 -5002x + 1 = 0
    (x - 2501)^2 - 2501^2 + 1 = 0 {complete the square}
    (x - 2501)^2 = 6255000
    x - 2501 = +/-sqrt(6255000)
    x = 2501 +/- 2500.9998
    x= 5001.9998 OR x = 1/5000
    i think.
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    (Original post by Revelation)
    5000x = 2^(x-1)
    5000x = (x-1)(x-1)
    I don't see how you've gone from the first line to the second :/.
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    (Original post by Nylex)
    I don't see how you've gone from the first line to the second :/.
    quite!
    You could say that 2^(x-1) = 2^x / 2 thats about it!
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    (Original post by username_)
    How would I go about solving this problem:
    5000x = 2^(x-1)

    Thanks
    Have you tried doing it by trial and error?
    I get x=17.4 (approx) - how accurate does it need to be?
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    On a similar vein, see this topic:
    http://www.uk-learning.net/showthread.php?t=24903

    I think that this equation is probably trancendental like ln(x)/x=c, so it will not be possible to solve algebraicly. Try a numerical approach.
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    (Original post by username_)
    How would I go about solving this problem:
    5000x = 2^(x-1)

    Thanks
    log5000+logx=(x-1)log2
    log5000+logx=xlog2-log1
    log5001=xlog2-logx

    You can do the rest.
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    (Original post by Bhaal85)
    log5000+logx=(x-1)log2
    log5000+logx=xlog2-log1
    log5001=xlog2-logx

    You can do the rest.
    J/k.

    This is actually quite a *****.

    5000X=2^(X-1)
    log5000+logX=(X-1)log2
    log5000+logX=Xlog2-log2
    log5000+log2=Xlog2-logX
    log(5000*2)=Xlog2-log2
    log(10000)=Xlog2-log2

    Now I'm stuck. :rolleyes:
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    (Original post by Bhaal85)
    J/k.

    This is actually quite a *****.

    5000X=2^(X-1)
    log5000+logX=(X-1)log2
    log5000+logX=Xlog2-log2
    log5000+log2=Xlog2-logX
    log(5000*2)=Xlog2-log2
    log(10000)=Xlog2-log2

    Now I'm stuck. :rolleyes:
    log10000=Xlog2/log2 therefire X = log10000???? :confused:
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    Numerical approach solutuion.
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    thnx foir replies. i tried doin it algebraically but kept hitting dead ends. thanks for explaining y it can't be solved algebraically too.
 
 
 

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