Integral of Exponents, Natural Logs...Date: 8/27/96 at 6:13:40 From: Wim De Blay Subject: Integral of Exponents, Natural Logs... Hi guys, Can you solve this integration? INT x^(-ln x).e^(-x.lnx + x).dx Date: 9/5/96 at 10:3:49 From: Doctor Jerry Subject: Re: Integral of Exponents, Natural Logs... I think it is likely that this integral can't be done in finite terms. I say this since if you make the substitution ln(x) = z, the integral becomes (using e^w to denote exp(w)) (**) int(e^(-z^2)*e^(e^z) dz). Since it is known that the integral int(e^(-z^2) dz) can't be done in finite terms (it is closely related to the normal probability density function and to the error function erf), it seems likely to me that the more complex integral (**) also can't be done in finite terms. -Doctor Jerry, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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