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Math Help - Logarithm Equation

  1. #1
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    Logarithm Equation

    has the solution x=
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  2. #2
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    Quote Originally Posted by thebristolsound View Post
    has the solution x=
    Use the fact that ln(a) - ln(b) = ln(\frac{a}{b})

    And: e^{ln(a)} = a

    To find the solution.
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  3. #3
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    Recall the rule lnA - lnB =ln(A/B). Apply that to LHS.
    Then you'll have ln [(x+1)/(x-2)} = ln x
    Drop the lns so that (x+1)/(x-2)=x
    This becomes x+1 = x(x-2) which gives a quadratic and go from there.

    Remember to check your answers from the quadratic in the ORIGINAL log equation. Reject answers which don't give pos values for x+1, x-2 or x as ln A is not defined for non-positive A valus.
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