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    How would you find x when:

    (x+3/x-2) = e ?

    Thanks in advance
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    I never used logs, instead I rearranged the left to say that 1 +(5/x-2) = e and solved from there. Not sure if this is allowed in C3 though :/
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    (Original post by mithili02)
    How would you find x when:

    (x+3/x-2) = e ?

    Thanks in advance
    How far have you got? Post your working.
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    Logs are necessary here. It's like using logs to solve  x^2=9 .
    Now e is just a constant so this is k=just like solving  \displaystyle \frac{x+3}{x-3} =5 as an example.
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    You can get the answer for this without logs. Try multiplying both sides by the denominator, expand RHS, rearrange to get the x on one side and then factorise to get x(....), then divide both sides by the (....) to get x=.....

    I just checked on the calculator and that works (sorry if that wasn't very clear)

    You could take ln of both sides and since ln(a/b) = ln(a-b) you can:

    rewrite as ln(x+3) - ln(x-2) = ln(e)

    add ln(x-2) to both sides

    ln(x+3) = ln(e) + ln(x-2)

    [ as ln(a) + ln(b)= ln(ab) ]

    ln(x+3) = ln(e(x-2))

    take e both sides to get

    x+3 = e(x-2)

    which is the same as if you just rearrange
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    Thankyouthankyou
 
 
 
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