Need Aproximate expressions for : ln(x) and 1/ln(x) Thanks

Boudy · Nov 1, 2017

Hi there:
I am looking for approximate expressions for the two functions: ln(x) and 1/ln(x) . Any help?
Thanks in advance.

mfb · Nov 1, 2017

Approximations where, for what? Did you try Taylor expansions?

mathman · Nov 1, 2017

ln(x) is not analytic at x=0. You need to use a series around some other value. If you use the series for ln((1+x)/(1-x)) you will able to get a series for any y=(1+x)/(1-x) for -1<x<1.

Need Aproximate expressions for : ln(x) and 1/ln(x) Thanks

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