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sin(10*x)/tan(5*x)

Limit of the function sin(10*x)/tan(5*x)

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     /sin(10*x)\
 lim |---------|
x->0+\ tan(5*x)/
limx0+(sin(10x)tan(5x))\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right)
Limit(sin(10*x)/tan(5*x), x, 0)
Detail solution
Let's take the limit
limx0+(sin(10x)tan(5x))\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right)
transform
limx0+(sin(10x)tan(5x))=limx0+(sin(10x)xxtan(5x))\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right) = \lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{x} \frac{x}{\tan{\left(5 x \right)}}\right)
=
limx0+(sin(10x)x)limx0+(xtan(5x))\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{x}\right) \lim_{x \to 0^+}\left(\frac{x}{\tan{\left(5 x \right)}}\right)
=
Do replacement
u=10xu = 10 x
and
v=5xv = 5 x
then
limx0+(sin(10x)tan(5x))=limu0+(10sin(u)u)limv0+(v5tan(v))\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right) = \lim_{u \to 0^+}\left(\frac{10 \sin{\left(u \right)}}{u}\right) \lim_{v \to 0^+}\left(\frac{v}{5 \tan{\left(v \right)}}\right)
=
2limu0+(sin(u)u)limv0+(vtan(v))2 \lim_{u \to 0^+}\left(\frac{\sin{\left(u \right)}}{u}\right) \lim_{v \to 0^+}\left(\frac{v}{\tan{\left(v \right)}}\right)
=
2limu0+(sin(u)u)(limv0+(tan(v)v))12 \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
limv0+(tan(v)v)=limv0+(sin(v)vcos(v))\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)
=
limv0+(sin(v)v)limv0+1cos(v)=limv0+(sin(v)v)\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
limu0+(sin(u)u)\lim_{u \to 0^+}\left(\frac{\sin{\left(u \right)}}{u}\right)
is first remarkable limit, is equal to 1.

The final answer:
limx0+(sin(10x)tan(5x))=2\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right) = 2
Lopital's rule
We have indeterminateness of type
0/0,

i.e. limit for the numerator is
limx0+sin(10x)=0\lim_{x \to 0^+} \sin{\left(10 x \right)} = 0
and limit for the denominator is
limx0+tan(5x)=0\lim_{x \to 0^+} \tan{\left(5 x \right)} = 0
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
limx0+(sin(10x)tan(5x))\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right)
=
limx0+(ddxsin(10x)ddxtan(5x))\lim_{x \to 0^+}\left(\frac{\frac{d}{d x} \sin{\left(10 x \right)}}{\frac{d}{d x} \tan{\left(5 x \right)}}\right)
=
limx0+(10cos(10x)5tan2(5x)+5)\lim_{x \to 0^+}\left(\frac{10 \cos{\left(10 x \right)}}{5 \tan^{2}{\left(5 x \right)} + 5}\right)
=
limx0+(105tan2(5x)+5)\lim_{x \to 0^+}\left(\frac{10}{5 \tan^{2}{\left(5 x \right)} + 5}\right)
=
limx0+(105tan2(5x)+5)\lim_{x \to 0^+}\left(\frac{10}{5 \tan^{2}{\left(5 x \right)} + 5}\right)
=
22
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
02468-8-6-4-2-101004
Rapid solution [src]
2
22
Other limits x→0, -oo, +oo, 1
limx0(sin(10x)tan(5x))=2\lim_{x \to 0^-}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right) = 2
More at x→0 from the left
limx0+(sin(10x)tan(5x))=2\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right) = 2
limx(sin(10x)tan(5x))\lim_{x \to \infty}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right)
More at x→oo
limx1(sin(10x)tan(5x))=sin(10)tan(5)\lim_{x \to 1^-}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right) = \frac{\sin{\left(10 \right)}}{\tan{\left(5 \right)}}
More at x→1 from the left
limx1+(sin(10x)tan(5x))=sin(10)tan(5)\lim_{x \to 1^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right) = \frac{\sin{\left(10 \right)}}{\tan{\left(5 \right)}}
More at x→1 from the right
limx(sin(10x)tan(5x))\lim_{x \to -\infty}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right)
More at x→-oo
One‐sided limits [src]
     /sin(10*x)\
 lim |---------|
x->0+\ tan(5*x)/
limx0+(sin(10x)tan(5x))\lim_{x \to 0^+}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right)
2
22
= 2.0
     /sin(10*x)\
 lim |---------|
x->0-\ tan(5*x)/
limx0(sin(10x)tan(5x))\lim_{x \to 0^-}\left(\frac{\sin{\left(10 x \right)}}{\tan{\left(5 x \right)}}\right)
2
22
= 2.0
= 2.0
Numerical answer [src]
2.0
2.0
The graph
Limit of the function sin(10*x)/tan(5*x)