mathmonster
I am trying to get the integral



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mathmonster
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I am writingit now

mathmonster
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\[\int\limits_{2}^{4} \left(\begin{matrix}dx \\ /x(lnx)^2\end{matrix}\right)\]

mathmonster
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that slash means division

abtrehearn
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Let u = ln x, du = dx/x, and substitute into the original integral to reduce it to something more recognizable.

mathmonster
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so, let = 1nx, okay let me try that, cause i have been letting u = (lnx)^2 and its been a nightmare

abtrehearn
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I think that plain ln x for u will be munc less of a nightmare.

mathmonster
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so in did that and got so far u^1/1

abtrehearn
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That's the same as\[\int\limits_{}^{}du/u.\]

abtrehearn
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Familiar?

mathmonster
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yup

abtrehearn
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Get it back to original x and you're done.

mathmonster
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i am still stuck at this part: \[\int\limits_{2}^{4} du/u^2\]

mathmonster
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i got it

abtrehearn
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Power formula. Rewrite as\[\int\limits_{}^{}u^{2}du\]

abtrehearn
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:^)