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What is the value of integral $\ln x$? Example:

$$\int_2^4 \left(5x^4+2x+5+2\ln x +{1\over x}\right)\,dx$$

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    have you tried wikipedia?2012-11-14
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    http://en.wikipedia.org/wiki/List_of_integrals_of_logarithmic_functions2012-11-14
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    I can't find it on wikipedia2012-11-14
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    i just posted a link as comment2012-11-14

2 Answers 2

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I guess what you are looking for is an antiderivative of $\ln(x)$. It is $$ \int \ln(x) \; dx = x\ln(x) -x +C. $$

This should allow you do find the integral.

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Hint: use integration by parts.

Another hint is greyed out below (hover over the box to show it, but only after you've tried!)

$\displaystyle \int \ln x\, dx = \int (1 \times \ln x)\, dx$