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Math Help - logarithic

  1. #1
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    Post logarithic

    5= 3lnx - 1/2lnx

    I assume you have to get both sides of the equation with the same term first. If I multiply by lnx, wouldn't it cancel out on the right side? The same for if I divide?
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  2. #2
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    Quote Originally Posted by startingover View Post
    5= 3lnx - 1/2lnx

    I assume you have to get both sides of the equation with the same term first. If I multiply by lnx, wouldn't it cancel out on the right side? The same for if I divide?
    Look at it this way:
    Let y = ln(x)
    Then:
    5 = 3y - (1/2)y

    5 = (5/2)y

    y = 5*2/5 = 2

    ln(x) = 2

    x = e^2

    -Dan
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  3. #3
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    Hello, startingover!

    Dan is absolutely correct.


    5 .= .3Ěln(x) - ŻĚln(x)
    Why are you trying to "cancel"?


    We have: .3Ěln(x) - ŻĚln(x) .= .5

    Combine: . . . . .(5/2)Ěln(x) .= .5

    Multiply by 2/5: . . . . ln(x) .= .2

    Therefore: . . . . . . . . . . x .= .e▓

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