How could I evaluate this IMPROPER integra?

Thread starter frasifrasi
Start date Nov 3, 2007

Nov 3, 2007

frasifrasi

Int from 1 to infinity of ln(X)/x^(3)

--> Any ideas on how to get started(mainly the technique)? thank you.

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Nov 3, 2007

Dick

Science Advisor

Homework Helper

You would first find an indefinite integral using integration by parts.

Nov 4, 2007

benjyk

Let u = ln x and dv/dx = x^-3 and use integration by parts.
And see what happens as the upper bound of the integral tends to infinity.

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