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    Hi, I have a few questions from P2 that I'm stuck with, so if anyone could help that would be great.

    1. Find value of y to 2d.p:
    ln(y+1) - lny = 0.85
    Whenever I do it I end up with y's that cancel out! grrrr

    2.Is e^(x-2) the same as e^x divided by e^2 (using indice rules)? Because I have a question where I have to find the inverse function of f(x)=e^(x-2) - 1 and I wasn't entirely sure what happens when I ln the equation, to get x.

    Thanks ever so much
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    (Original post by Hoofbeat)
    Hi, I have a few questions from P2 that I'm stuck with, so if anyone could help that would be great.

    1. Find value of y to 2d.p:
    ln(y+1) - lny = 0.85
    Whenever I do it I end up with y's that cancel out! grrrr

    2.Is e^(x-2) the same as e^x divided by e^2 (using indice rules)? Because I have a question where I have to find the inverse function of f(x)=e^(x-2) - 1 and I wasn't entirely sure what happens when I ln the equation, to get x.

    Thanks ever so much
    1. ln (y + 1) - ln y = 0.85

    => ln |(y + 1)/y| = 0.85

    (y + 1)/y = e^0.85

    (y + 1)/y = 2.3396

    2.3396y = y + 1

    2.3396y - y = 1

    y(2.3396 - 1) = 1

    y = 1/1.3396
    y = 0.75

    2. Yes, it is.
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    (Original post by Nylex)
    1. ln (y + 1) - ln y = 0.85

    => ln |(y + 1)/y| = 0.85

    (y + 1)/y = e^0.85

    (y + 1)/y = 2.3396

    2.3396y = y + 1

    2.3396y - y = 1

    y(2.3396 - 1) = 1

    y = 1/1.3396
    y = 0.75

    2. Yes, it is.
    You're a star!!!!!!!!!! (((HUGZ))) Thanks so much!
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    No prob .
 
 
 
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