Integral of (x + 1/x) * ln(x) dx

Limits, differentiation, related rates, integration, trig integrals, etc.
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Integral of (x + 1/x) * ln(x) dx

Postby mitnord » Thu Mar 26, 2009 2:25 am

Help me solve the integral of (x + 1/x) * ln(x) dx

Keep going in circles, Calculus 1. semester.

Thank you.

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Postby stapel_eliz » Thu Mar 26, 2009 3:06 pm

mitnord wrote:Keep going in circles

What were the "circles"? (You'd be surprised how often an apparent "circle" is actually leading to the solution!) :wink:

mitnord wrote:Help me solve the integral of (x + 1/x) * ln(x) dx

It might help to break this into two integrals:

. . . .

The second integral, I2, should be simple enough. :wink: It's the other one that's a bit of a bear. I would suggest integration by parts, with:

. . . .

Hope that helps! :D

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