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Math Help - stuck with a logarithm

  1. #1
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    stuck with a logarithm

    Hi;
    Solve for x: 4log(x - 6) = 11

    so far I'm hare log(x - 6)^4 = 11 (not sure where to go from here).

    Thanks.
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  2. #2
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    Re: stuck with a logarithm

    Apply the function inverse to log to both sides.
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  3. #3
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    Re: stuck with a logarithm

    Yeah I got it thanks.
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  4. #4
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    Re: stuck with a logarithm

    The inverse of log_a(x) is a^x- that is if y= log_a(x) then x= a^y. Your problem is a little ambiguous because you do not give a base for the logarithm. Normally, that would imply the "common logarithm", base 10. If that is the base here, then (x- 6)^4= 10^{11}. That is probably correct here but in higher level mathematics it is common to use "log" rather than "ln" to mean the natural logarithm. If that is the case, then (x- 6)^4= e^{11}.
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