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cos(x)*sin(x)/x

Limit of the function cos(x)*sin(x)/x

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

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