By easy, I mean for people that are good at this. I spent 30 minutes thinking prior to posting here $\displaystyle \frac{1}{xln^3x}dx $ This looks like u = ln(x) or something but that extra x is messing me up
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Originally Posted by TYTY By easy, I mean for people that are good at this. I spent 30 minutes thinking prior to posting here $\displaystyle \frac{1}{xln^3x}dx $ This looks like u = ln(x) or something but that extra x is messing me up You have the correct substituion $\displaystyle u=\ln(x) \implies du=\frac{1}{x}dx$ putting these into the integral gives $\displaystyle \int \frac{1}{u^3}du=\int u^{-3}du$ Good luck.
Originally Posted by TheEmptySet You have the correct substituion $\displaystyle u=\ln(x) \implies du=\frac{1}{x}dx$ putting these into the integral gives $\displaystyle \int \frac{1}{u^3}du=\int u^{-3}du$ Good luck. I'm actually a little bit upset that it was that easy. Thank you though - I do appreciate it
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