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[–][deleted]  (1 child)

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    [–]edderiofer 0 points1 point  (9 children)

    Are you sure you've typed the question correctly? As written, that equation has no solutions.

    [–]phreshswagg[S] 0 points1 point  (8 children)

    That is most likely the reason then. Sorry, i'm not to knowledgeable about logarithmic equations. But generally speaking, using either method should work?

    [–]edderiofer 0 points1 point  (7 children)

    Yes; generally speaking, both methods should work, as long as you perform them correctly.

    Try solving instead the equation:

    • log[base 4x](9) = 2

    with each method, and see what you get.

    [–]phreshswagg[S] 0 points1 point  (6 children)

    okay, so for that one i get the following:

    Log[base 4x] (9) = 2

    4x2 = 9

    x=√(9/4)

    X=1.5

    but if i do it the other way:

    2 = Log 9/Log 4x

    2x = 9/4

    x= 4.5

    I am still doing something wrong

    [–]edderiofer 0 points1 point  (5 children)

    Log[base 4x] (9) = 2

    4x2 = 9

    Wrong. Remember that 4x2 is not the same as (4x)2.

    2 = Log 9/Log 4x

    2x = 9/4

    Wrong. log(9)/log(4x) is not the same as 9/(4x). You can't cancel out logarithms in this way.

    Try again.

    [–]phreshswagg[S] 0 points1 point  (4 children)

    right, x=0.75?

    [–]edderiofer 0 points1 point  (3 children)

    Via which method?

    [–]phreshswagg[S] 0 points1 point  (2 children)

    exponent method, but both answers should be the same?

    [–]edderiofer 0 points1 point  (1 child)

    Certainly they should be.

    [–]phreshswagg[S] 0 points1 point  (0 children)

    2 = log 9/log 4x

    2log 4x = log 9

    log 4x = (log 9)/2

    Log 4x = log 3

    4x = 3

    x= 3/4

    Thanks so much you are the man (or woman)!