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Límite de la función cot(x)^2*sin(x)^2*(-sin(x)^(-2*x)/cot(x)^2+cos(x))

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Ha introducido [src]
     /                /    -2*x             \\
     |   2       2    |-sin    (x)          ||
 lim |cot (x)*sin (x)*|------------ + cos(x)||
x->0+|                |     2               ||
     \                \  cot (x)            //
$$\lim_{x \to 0^+}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right)$$
Limit((cot(x)^2*sin(x)^2)*((-sin(x)^(-2*x))/cot(x)^2 + cos(x)), x, 0)
Método de l'Hopital
Tenemos la indeterminación de tipo
0/0,

tal que el límite para el numerador es
$$\lim_{x \to 0^+} \sin^{2 - 2 x}{\left(x \right)} = 0$$
y el límite para el denominador es
$$\lim_{x \to 0^+} \frac{1}{\sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{2}{\left(x \right)} - 1} = 0$$
Vamos a probar las derivadas del numerador y denominador hasta eliminar la indeterminación.
$$\lim_{x \to 0^+}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right)$$
=
Introducimos una pequeña modificación de la función bajo el signo del límite
$$\lim_{x \to 0^+}\left(\left(\sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{2}{\left(x \right)} - 1\right) \sin^{2}{\left(x \right)} \sin^{- 2 x}{\left(x \right)}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{\frac{d}{d x} \sin^{2 - 2 x}{\left(x \right)}}{\frac{d}{d x} \frac{1}{\sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{2}{\left(x \right)} - 1}}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{\left(- 2 x \sin{\left(x \right)} \sin^{4 x}{\left(x \right)} \cos^{3}{\left(x \right)} \cot^{4}{\left(x \right)} + 4 x \sin{\left(x \right)} \sin^{2 x}{\left(x \right)} \cos^{2}{\left(x \right)} \cot^{2}{\left(x \right)} - 2 x \sin{\left(x \right)} \cos{\left(x \right)} - 2 \log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)} \sin^{4 x}{\left(x \right)} \cos^{2}{\left(x \right)} \cot^{4}{\left(x \right)} + 4 \log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)} \sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{2}{\left(x \right)} - 2 \log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)} + 2 \sin{\left(x \right)} \sin^{4 x}{\left(x \right)} \cos^{3}{\left(x \right)} \cot^{4}{\left(x \right)} - 4 \sin{\left(x \right)} \sin^{2 x}{\left(x \right)} \cos^{2}{\left(x \right)} \cot^{2}{\left(x \right)} + 2 \sin{\left(x \right)} \cos{\left(x \right)}\right) \sin^{- 2 x}{\left(x \right)}}{- \frac{2 x \sin^{2 x}{\left(x \right)} \cos^{2}{\left(x \right)} \cot^{2}{\left(x \right)}}{\sin{\left(x \right)}} - 2 \log{\left(\sin{\left(x \right)} \right)} \sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{2}{\left(x \right)} + \sin{\left(x \right)} \sin^{2 x}{\left(x \right)} \cot^{2}{\left(x \right)} + 2 \sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{3}{\left(x \right)} + 2 \sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot{\left(x \right)}}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{\left(- 2 x \sin{\left(x \right)} \sin^{4 x}{\left(x \right)} \cos^{3}{\left(x \right)} \cot^{4}{\left(x \right)} + 4 x \sin{\left(x \right)} \sin^{2 x}{\left(x \right)} \cos^{2}{\left(x \right)} \cot^{2}{\left(x \right)} - 2 x \sin{\left(x \right)} \cos{\left(x \right)} - 2 \log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)} \sin^{4 x}{\left(x \right)} \cos^{2}{\left(x \right)} \cot^{4}{\left(x \right)} + 4 \log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)} \sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{2}{\left(x \right)} - 2 \log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)} + 2 \sin{\left(x \right)} \sin^{4 x}{\left(x \right)} \cos^{3}{\left(x \right)} \cot^{4}{\left(x \right)} - 4 \sin{\left(x \right)} \sin^{2 x}{\left(x \right)} \cos^{2}{\left(x \right)} \cot^{2}{\left(x \right)} + 2 \sin{\left(x \right)} \cos{\left(x \right)}\right) \sin^{- 2 x}{\left(x \right)}}{- \frac{2 x \sin^{2 x}{\left(x \right)} \cos^{2}{\left(x \right)} \cot^{2}{\left(x \right)}}{\sin{\left(x \right)}} - 2 \log{\left(\sin{\left(x \right)} \right)} \sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{2}{\left(x \right)} + \sin{\left(x \right)} \sin^{2 x}{\left(x \right)} \cot^{2}{\left(x \right)} + 2 \sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot^{3}{\left(x \right)} + 2 \sin^{2 x}{\left(x \right)} \cos{\left(x \right)} \cot{\left(x \right)}}\right)$$
=
$$1$$
Como puedes ver, hemos aplicado el método de l'Hopital (utilizando la derivada del numerador y denominador) 1 vez (veces)
Gráfica
Respuesta rápida [src]
1
$$1$$
A la izquierda y a la derecha [src]
     /                /    -2*x             \\
     |   2       2    |-sin    (x)          ||
 lim |cot (x)*sin (x)*|------------ + cos(x)||
x->0+|                |     2               ||
     \                \  cot (x)            //
$$\lim_{x \to 0^+}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right)$$
1
$$1$$
= 0.999999694003347
     /                /    -2*x             \\
     |   2       2    |-sin    (x)          ||
 lim |cot (x)*sin (x)*|------------ + cos(x)||
x->0-|                |     2               ||
     \                \  cot (x)            //
$$\lim_{x \to 0^-}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right)$$
1
$$1$$
= (1.00000000007584 - 4.06043005141319e-13j)
= (1.00000000007584 - 4.06043005141319e-13j)
Otros límites con x→0, -oo, +oo, 1
$$\lim_{x \to 0^-}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right) = 1$$
Más detalles con x→0 a la izquierda
$$\lim_{x \to 0^+}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right) = 1$$
$$\lim_{x \to \infty}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right)$$
Más detalles con x→oo
$$\lim_{x \to 1^-}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right) = \frac{- \tan^{2}{\left(1 \right)} + \sin^{2}{\left(1 \right)} \cos{\left(1 \right)}}{\tan^{2}{\left(1 \right)}}$$
Más detalles con x→1 a la izquierda
$$\lim_{x \to 1^+}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right) = \frac{- \tan^{2}{\left(1 \right)} + \sin^{2}{\left(1 \right)} \cos{\left(1 \right)}}{\tan^{2}{\left(1 \right)}}$$
Más detalles con x→1 a la derecha
$$\lim_{x \to -\infty}\left(\sin^{2}{\left(x \right)} \cot^{2}{\left(x \right)} \left(\frac{\left(-1\right) \sin^{- 2 x}{\left(x \right)}}{\cot^{2}{\left(x \right)}} + \cos{\left(x \right)}\right)\right)$$
Más detalles con x→-oo
Respuesta numérica [src]
0.999999694003347
0.999999694003347