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haywood
Sep16-08, 02:14 AM
Can anyone tell me how to find a two-term asymptotic expansion for the two real roots of xe-x=epsilon as epsilon --> 0

Thanks,
A.Haywood

dalle
Sep17-08, 02:20 PM
dear Haywood
I don't know what kind of asypmtotic expasion you are looking for, so a short hint on how to solve the equation approximatly must suffice.
For the root near 0 substitute the left hand side with a taylor polynomial.
For the other root take logarithms on both sides.

haywood
Sep21-08, 02:00 AM
That works!!! I was especially looking for how to find that second root, so grateful that you mentioned using ln :-)
Thank you, Dalle!