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What is the antiderivative of

$$\int\frac{1}{r \ln(r)} \ dr$$

I'm trying to use substitution, but substituting $u=r$ doesn't help as that just changes the variable.

  • 2
    Try using $u=\ln(r)$.2012-12-11
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    One last hint: $\dfrac{1}{r \ln r} = \dfrac{1}{r} \cdot \dfrac{1}{\ln r}$.2012-12-11

2 Answers 2