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    Hi, I was just wondering how to solve x for e^(-x) - x +1 = 0. ty
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    (Original post by SlyClick)
    Hi, I was just wondering how to solve x for e^(-x) - x +1 = 0. ty
    Numerical methods.

    You won't get a solution with elementary functions.
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    (Original post by SlyClick)
    Hi, I was just wondering how to solve x for e^(-x) - x +1 = 0. ty
    Just to build on the last post (which is accurate).

    If you want to find a good approximation for the solution in a pretty simple way you could write only the first 2 or 3 terms of the expansion of e^(-x) and then use the general formula for quadratics/cubics
    to solve it for x. This will give you something pretty close (why?).

    You could make it even more accurate by finding the Taylor series of exp around x=1 and use that


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