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sin(3*x)/tan(3*x)

Limit of the function sin(3*x)/tan(3*x)

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     /sin(3*x)\
 lim |--------|
x->0+\tan(3*x)/
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right)$$
Limit(sin(3*x)/tan(3*x), x, 0)
Detail solution
Let's take the limit
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right)$$
transform
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right) = \lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{x} \frac{x}{\tan{\left(3 x \right)}}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{x}\right) \lim_{x \to 0^+}\left(\frac{x}{\tan{\left(3 x \right)}}\right)$$
=
Do replacement
$$u = 3 x$$
and
$$v = 3 x$$
then
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right) = \lim_{u \to 0^+}\left(\frac{3 \sin{\left(u \right)}}{u}\right) \lim_{v \to 0^+}\left(\frac{v}{3 \tan{\left(v \right)}}\right)$$
=
$$\lim_{u \to 0^+}\left(\frac{\sin{\left(u \right)}}{u}\right) \lim_{v \to 0^+}\left(\frac{v}{\tan{\left(v \right)}}\right)$$
=
$$\lim_{u \to 0^+}\left(\frac{\sin{\left(u \right)}}{u}\right) \left(\lim_{v \to 0^+}\left(\frac{\tan{\left(v \right)}}{v}\right)\right)^{-1}$$
transform
$$\lim_{v \to 0^+}\left(\frac{\tan{\left(v \right)}}{v}\right) = \lim_{v \to 0^+}\left(\frac{\sin{\left(v \right)}}{v \cos{\left(v \right)}}\right)$$
=
$$\lim_{v \to 0^+}\left(\frac{\sin{\left(v \right)}}{v}\right) \lim_{v \to 0^+} \frac{1}{\cos{\left(v \right)}} = \lim_{v \to 0^+}\left(\frac{\sin{\left(v \right)}}{v}\right)$$
The limit
$$\lim_{u \to 0^+}\left(\frac{\sin{\left(u \right)}}{u}\right)$$
is first remarkable limit, is equal to 1.

The final answer:
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right) = 1$$
Lopital's rule
We have indeterminateness of type
0/0,

i.e. limit for the numerator is
$$\lim_{x \to 0^+} \sin{\left(3 x \right)} = 0$$
and limit for the denominator is
$$\lim_{x \to 0^+} \tan{\left(3 x \right)} = 0$$
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{\frac{d}{d x} \sin{\left(3 x \right)}}{\frac{d}{d x} \tan{\left(3 x \right)}}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{3 \cos{\left(3 x \right)}}{3 \tan^{2}{\left(3 x \right)} + 3}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{3}{3 \tan^{2}{\left(3 x \right)} + 3}\right)$$
=
$$\lim_{x \to 0^+}\left(\frac{3}{3 \tan^{2}{\left(3 x \right)} + 3}\right)$$
=
$$1$$
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
One‐sided limits [src]
     /sin(3*x)\
 lim |--------|
x->0+\tan(3*x)/
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right)$$
1
$$1$$
= 1.0
     /sin(3*x)\
 lim |--------|
x->0-\tan(3*x)/
$$\lim_{x \to 0^-}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right)$$
1
$$1$$
= 1.0
= 1.0
Rapid solution [src]
1
$$1$$
Other limits x→0, -oo, +oo, 1
$$\lim_{x \to 0^-}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right) = 1$$
More at x→0 from the left
$$\lim_{x \to 0^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right) = 1$$
$$\lim_{x \to \infty}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right)$$
More at x→oo
$$\lim_{x \to 1^-}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right) = \frac{\sin{\left(3 \right)}}{\tan{\left(3 \right)}}$$
More at x→1 from the left
$$\lim_{x \to 1^+}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right) = \frac{\sin{\left(3 \right)}}{\tan{\left(3 \right)}}$$
More at x→1 from the right
$$\lim_{x \to -\infty}\left(\frac{\sin{\left(3 x \right)}}{\tan{\left(3 x \right)}}\right)$$
More at x→-oo
Numerical answer [src]
1.0
1.0
The graph
Limit of the function sin(3*x)/tan(3*x)