Mister Exam

Other calculators:

Limit of the function log(factorial(x))/x

at
v

For end points:

The graph:

from to

Piecewise:

The solution

You have entered [src]
     /log(x!)\
 lim |-------|
x->oo\   x   /
limx(log(x!)x)\lim_{x \to \infty}\left(\frac{\log{\left(x! \right)}}{x}\right)
Limit(log(factorial(x))/x, x, oo, dir='-')
Lopital's rule
We have indeterminateness of type
oo/oo,

i.e. limit for the numerator is
limxlog(x!)=\lim_{x \to \infty} \log{\left(x! \right)} = \infty
and limit for the denominator is
limxx=\lim_{x \to \infty} x = \infty
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
limx(log(x!)x)\lim_{x \to \infty}\left(\frac{\log{\left(x! \right)}}{x}\right)
=
limx(ddxlog(x!)ddxx)\lim_{x \to \infty}\left(\frac{\frac{d}{d x} \log{\left(x! \right)}}{\frac{d}{d x} x}\right)
=
limx(Γ(x+1)polygamma(0,x+1)x!)\lim_{x \to \infty}\left(\frac{\Gamma\left(x + 1\right) \operatorname{polygamma}{\left(0,x + 1 \right)}}{x!}\right)
=
limx(Γ(x+1)polygamma(0,x+1)x!)\lim_{x \to \infty}\left(\frac{\Gamma\left(x + 1\right) \operatorname{polygamma}{\left(0,x + 1 \right)}}{x!}\right)
=
\infty
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)
Rapid solution [src]
oo
\infty
Other limits x→0, -oo, +oo, 1
limx(log(x!)x)=\lim_{x \to \infty}\left(\frac{\log{\left(x! \right)}}{x}\right) = \infty
limx0(log(x!)x)=γ\lim_{x \to 0^-}\left(\frac{\log{\left(x! \right)}}{x}\right) = - \gamma
More at x→0 from the left
limx0+(log(x!)x)=γ\lim_{x \to 0^+}\left(\frac{\log{\left(x! \right)}}{x}\right) = - \gamma
More at x→0 from the right
limx1(log(x!)x)=0\lim_{x \to 1^-}\left(\frac{\log{\left(x! \right)}}{x}\right) = 0
More at x→1 from the left
limx1+(log(x!)x)=0\lim_{x \to 1^+}\left(\frac{\log{\left(x! \right)}}{x}\right) = 0
More at x→1 from the right
limx(log(x!)x)=0\lim_{x \to -\infty}\left(\frac{\log{\left(x! \right)}}{x}\right) = 0
More at x→-oo