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Límite de la función log(1+x)^(1+x)-1/x^2

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Ha introducido [src]
     /   1 + x          1 \
 lim |log     (1 + x) - --|
x->oo|                   2|
     \                  x /
$$\lim_{x \to \infty}\left(\log{\left(x + 1 \right)}^{x + 1} - \frac{1}{x^{2}}\right)$$
Limit(log(1 + x)^(1 + x) - 1/x^2, x, oo, dir='-')
Método de l'Hopital
Tenemos la indeterminación de tipo
oo/oo,

tal que el límite para el numerador es
$$\lim_{x \to \infty}\left(x^{2} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} - 1\right) = \infty$$
y el límite para el denominador es
$$\lim_{x \to \infty} x^{2} = \infty$$
Vamos a probar las derivadas del numerador y denominador hasta eliminar la indeterminación.
$$\lim_{x \to \infty}\left(\log{\left(x + 1 \right)}^{x + 1} - \frac{1}{x^{2}}\right)$$
=
Introducimos una pequeña modificación de la función bajo el signo del límite
$$\lim_{x \to \infty}\left(\frac{x^{2} \log{\left(x + 1 \right)}^{x + 1} - 1}{x^{2}}\right)$$
=
$$\lim_{x \to \infty}\left(\frac{\frac{d}{d x} \left(x^{2} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} - 1\right)}{\frac{d}{d x} x^{2}}\right)$$
=
$$\lim_{x \to \infty}\left(\frac{\frac{x^{3} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{x \log{\left(x + 1 \right)} + \log{\left(x + 1 \right)}} + x^{2} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)} + \frac{x^{2} \log{\left(x + 1 \right)}^{x}}{x + 1} + 2 x \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 x}\right)$$
=
$$\lim_{x \to \infty}\left(\frac{\frac{d}{d x} \left(\frac{x^{3} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{x \log{\left(x + 1 \right)} + \log{\left(x + 1 \right)}} + x^{2} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)} + \frac{x^{2} \log{\left(x + 1 \right)}^{x}}{x + 1} + 2 x \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}\right)}{\frac{d}{d x} 2 x}\right)$$
=
$$\lim_{x \to \infty}\left(- \frac{x^{4} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 x^{3} \log{\left(x + 1 \right)}^{2} + 6 x^{2} \log{\left(x + 1 \right)}^{2} + 6 x \log{\left(x + 1 \right)}^{2} + 2 \log{\left(x + 1 \right)}^{2}} + \frac{x^{4} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 \left(x^{2} \log{\left(x + 1 \right)}^{2} + 2 x \log{\left(x + 1 \right)}^{2} + \log{\left(x + 1 \right)}^{2}\right)} - \frac{x^{3} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 x^{3} \log{\left(x + 1 \right)}^{2} + 6 x^{2} \log{\left(x + 1 \right)}^{2} + 6 x \log{\left(x + 1 \right)}^{2} + 2 \log{\left(x + 1 \right)}^{2}} - \frac{x^{3} \log{\left(x + 1 \right)}^{2} \log{\left(x + 1 \right)}^{x}}{2 \left(x^{2} \log{\left(x + 1 \right)}^{2} + 2 x \log{\left(x + 1 \right)}^{2} + \log{\left(x + 1 \right)}^{2}\right)} + \frac{2 x^{3} \log{\left(x + 1 \right)}^{x}}{2 x^{2} \log{\left(x + 1 \right)} + 4 x \log{\left(x + 1 \right)} + 2 \log{\left(x + 1 \right)}} + \frac{x^{3} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)}}{x \log{\left(x + 1 \right)} + \log{\left(x + 1 \right)}} + \frac{x^{2} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)}^{2}}{2} - \frac{x^{2} \log{\left(x + 1 \right)}^{x}}{2 \left(x^{2} + 2 x + 1\right)} + \frac{5 x^{2} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 \left(x \log{\left(x + 1 \right)} + \log{\left(x + 1 \right)}\right)} + \frac{x^{2} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)}}{x + 1} + \frac{x^{2} \log{\left(x + 1 \right)}^{x}}{2 \left(x + 1\right)} + 2 x \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)} + \frac{2 x \log{\left(x + 1 \right)}^{x}}{x + 1} + \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}\right)$$
=
$$\lim_{x \to \infty}\left(- \frac{x^{4} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 x^{3} \log{\left(x + 1 \right)}^{2} + 6 x^{2} \log{\left(x + 1 \right)}^{2} + 6 x \log{\left(x + 1 \right)}^{2} + 2 \log{\left(x + 1 \right)}^{2}} + \frac{x^{4} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 \left(x^{2} \log{\left(x + 1 \right)}^{2} + 2 x \log{\left(x + 1 \right)}^{2} + \log{\left(x + 1 \right)}^{2}\right)} - \frac{x^{3} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 x^{3} \log{\left(x + 1 \right)}^{2} + 6 x^{2} \log{\left(x + 1 \right)}^{2} + 6 x \log{\left(x + 1 \right)}^{2} + 2 \log{\left(x + 1 \right)}^{2}} - \frac{x^{3} \log{\left(x + 1 \right)}^{2} \log{\left(x + 1 \right)}^{x}}{2 \left(x^{2} \log{\left(x + 1 \right)}^{2} + 2 x \log{\left(x + 1 \right)}^{2} + \log{\left(x + 1 \right)}^{2}\right)} + \frac{2 x^{3} \log{\left(x + 1 \right)}^{x}}{2 x^{2} \log{\left(x + 1 \right)} + 4 x \log{\left(x + 1 \right)} + 2 \log{\left(x + 1 \right)}} + \frac{x^{3} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)}}{x \log{\left(x + 1 \right)} + \log{\left(x + 1 \right)}} + \frac{x^{2} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)}^{2}}{2} - \frac{x^{2} \log{\left(x + 1 \right)}^{x}}{2 \left(x^{2} + 2 x + 1\right)} + \frac{5 x^{2} \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}}{2 \left(x \log{\left(x + 1 \right)} + \log{\left(x + 1 \right)}\right)} + \frac{x^{2} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)}}{x + 1} + \frac{x^{2} \log{\left(x + 1 \right)}^{x}}{2 \left(x + 1\right)} + 2 x \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x} \log{\left(\log{\left(x + 1 \right)} \right)} + \frac{2 x \log{\left(x + 1 \right)}^{x}}{x + 1} + \log{\left(x + 1 \right)} \log{\left(x + 1 \right)}^{x}\right)$$
=
$$\infty$$
Como puedes ver, hemos aplicado el método de l'Hopital (utilizando la derivada del numerador y denominador) 2 vez (veces)
Gráfica
Respuesta rápida [src]
oo
$$\infty$$
Otros límites con x→0, -oo, +oo, 1
$$\lim_{x \to \infty}\left(\log{\left(x + 1 \right)}^{x + 1} - \frac{1}{x^{2}}\right) = \infty$$
$$\lim_{x \to 0^-}\left(\log{\left(x + 1 \right)}^{x + 1} - \frac{1}{x^{2}}\right) = -\infty$$
Más detalles con x→0 a la izquierda
$$\lim_{x \to 0^+}\left(\log{\left(x + 1 \right)}^{x + 1} - \frac{1}{x^{2}}\right) = -\infty$$
Más detalles con x→0 a la derecha
$$\lim_{x \to 1^-}\left(\log{\left(x + 1 \right)}^{x + 1} - \frac{1}{x^{2}}\right) = -1 + \log{\left(2 \right)}^{2}$$
Más detalles con x→1 a la izquierda
$$\lim_{x \to 1^+}\left(\log{\left(x + 1 \right)}^{x + 1} - \frac{1}{x^{2}}\right) = -1 + \log{\left(2 \right)}^{2}$$
Más detalles con x→1 a la derecha
$$\lim_{x \to -\infty}\left(\log{\left(x + 1 \right)}^{x + 1} - \frac{1}{x^{2}}\right) = 0$$
Más detalles con x→-oo