Solving Limit: x.log(x) - Indetermination

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Homework Statement



The problem is

Limit [x.log(x)]
x->+oo

Homework Equations



Consider Log being a logarithm of base 10

This will tend to +oo, but x.log(x) will become (oo).(oo) which is an indetermination I need to know how to solve the indetermination in this case

The Attempt at a Solution



Thanks for all help
 
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\infty * \infty is NOT an indeterminate form. If you have two quantities that are getting larger and larger, their product will, too. The limit is infinity.
 
Bear in mind that
x\log(x) = \frac{\log(x)}{\frac{1}{x}}.
Given that form, you can apply l'Hopital's rule.
 
No, you can't. That becomes "infinity over 0" which, again, is NOT an "indeterminant". L'Hopilal's rule does not apply and you don't need it.
 
HallsofIvy said:
No, you can't. That becomes "infinity over 0" which, again, is NOT an "indeterminant". L'Hopilal's rule does not apply and you don't need it.

My apologies; read it too quickly and thought we were talking about a limit as x->0+.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

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