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cot(5*x)*sin(2*x)

Limit of the function cot(5*x)*sin(2*x)

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 lim (cot(5*x)*sin(2*x))
x->0+                   
$$\lim_{x \to 0^+}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right)$$
Limit(cot(5*x)*sin(2*x), x, 0)
Lopital's rule
We have indeterminateness of type
0/0,

i.e. limit for the numerator is
$$\lim_{x \to 0^+} \sin{\left(2 x \right)} = 0$$
and limit for the denominator is
$$\lim_{x \to 0^+} \frac{1}{\cot{\left(5 x \right)}} = 0$$
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
$$\lim_{x \to 0^+}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{\frac{d}{d x} \sin{\left(2 x \right)}}{\frac{d}{d x} \frac{1}{\cot{\left(5 x \right)}}}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{2 \cos{\left(2 x \right)} \cot^{2}{\left(5 x \right)}}{5 \cot^{2}{\left(5 x \right)} + 5}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{2 \cot^{2}{\left(5 x \right)}}{5 \cot^{2}{\left(5 x \right)} + 5}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{2 \cot^{2}{\left(5 x \right)}}{5 \cot^{2}{\left(5 x \right)} + 5}\right)$$
=
$$\frac{2}{5}$$
It can be seen that we have applied Lopital's rule (we have taken derivatives with respect to the numerator and denominator) 1 time(s)
The graph
Rapid solution [src]
2/5
$$\frac{2}{5}$$
One‐sided limits [src]
 lim (cot(5*x)*sin(2*x))
x->0+                   
$$\lim_{x \to 0^+}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right)$$
2/5
$$\frac{2}{5}$$
= 0.4
 lim (cot(5*x)*sin(2*x))
x->0-                   
$$\lim_{x \to 0^-}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right)$$
2/5
$$\frac{2}{5}$$
= 0.4
= 0.4
Other limits x→0, -oo, +oo, 1
$$\lim_{x \to 0^-}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right) = \frac{2}{5}$$
More at x→0 from the left
$$\lim_{x \to 0^+}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right) = \frac{2}{5}$$
$$\lim_{x \to \infty}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right)$$
More at x→oo
$$\lim_{x \to 1^-}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right) = \frac{\sin{\left(2 \right)}}{\tan{\left(5 \right)}}$$
More at x→1 from the left
$$\lim_{x \to 1^+}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right) = \frac{\sin{\left(2 \right)}}{\tan{\left(5 \right)}}$$
More at x→1 from the right
$$\lim_{x \to -\infty}\left(\sin{\left(2 x \right)} \cot{\left(5 x \right)}\right)$$
More at x→-oo
Numerical answer [src]
0.4
0.4
The graph
Limit of the function cot(5*x)*sin(2*x)