$\displaystyle \int\ln^2(x)dx$

Hints please? (Crying)

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- May 1st 2010, 01:57 PMiPodIntegral of ln Squared?
$\displaystyle \int\ln^2(x)dx$

Hints please? (Crying) - May 1st 2010, 02:11 PMTKHunny
Looks like a prime candidate for "Parts". It's almost an eyeball problem.

$\displaystyle x\cdot ln^{2}(x) - \int x\cdot 2\cdot ln(x)\cdot \frac{1}{x}\;dx$ - May 1st 2010, 02:15 PMiPod
soo,

$\displaystyle \ln^2(x)-2x\ln(x)+2x+C$

?? - May 1st 2010, 02:22 PMpickslides
close, try $\displaystyle x\ln^2(x)-2x\ln(x)+2x+C$

- May 1st 2010, 02:22 PMTKHunny
So close! Give it another go. This time, don't lose the 'x' on the front.

- May 1st 2010, 02:23 PMharish21
- May 1st 2010, 02:26 PMiPod
woopsy, that was a typo ^^

i meant to right

$\displaystyle x\ln^2(x)-2x\ln(x)+2x+C$

but I have seen what you have done tkhunny, using the 'by parts rule, you have integrated it as if it was

$\displaystyle \int1.\ln^2(x)$

right? - May 1st 2010, 02:30 PMpickslides
- May 1st 2010, 02:35 PMiPod
Thanks you lot :D

- May 1st 2010, 04:12 PMTKHunny
...except that I don't use that silly American method. The Russians are much more visual and literal.