math

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logarithms?

log (base 9) x+3 log (base 3) x=14

  • math -

    log9(x) = log3(x) * log9(3)
    what is log9(3)
    9^log9(3) = 3
    9^.5 = 3
    so
    log 9(x) = .5 log3(x)
    Now the problem
    .5 log3(x) + 3 log3(x) = 14
    log3 (x^.5) + log3(x^3) = 14
    log 3 (x^3.5) = 14
    x^3.5 = 3^14
    now use plain old base ten logs
    3.5 log x = 14 log 3
    log x = 1.91
    x = 10^1.91 = 81.3
    Check my arithmetic!!!

  • math -

    deeeeeeeeez ntus

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