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(1+n)^3/n^3

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(1+n)^3/n^3

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Limit of the function (1+n)^3/n^3

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     /       3\
     |(1 + n) |
 lim |--------|
n->oo|    3   |
     \   n    /
$$\lim_{n \to \infty}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right)$$
Limit((1 + n)^3/(n^3), n, oo, dir='-')
Detail solution
Let's take the limit
$$\lim_{n \to \infty}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right)$$
Let's divide numerator and denominator by n^3:
$$\lim_{n \to \infty}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right)$$ =
$$\lim_{n \to \infty}\left(\frac{1 + \frac{3}{n} + \frac{3}{n^{2}} + \frac{1}{n^{3}}}{1}\right)$$
Do Replacement
$$u = \frac{1}{n}$$
then
$$\lim_{n \to \infty}\left(\frac{1 + \frac{3}{n} + \frac{3}{n^{2}} + \frac{1}{n^{3}}}{1}\right) = \lim_{u \to 0^+}\left(u^{3} + 3 u^{2} + 3 u + 1\right)$$
=
$$0^{3} + 3 \cdot 0 + 3 \cdot 0^{2} + 1 = 1$$

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

i.e. limit for the numerator is
$$\lim_{n \to \infty} \left(n + 1\right)^{3} = \infty$$
and limit for the denominator is
$$\lim_{n \to \infty} n^{3} = \infty$$
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
$$\lim_{n \to \infty}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right)$$
=
Let's transform the function under the limit a few
$$\lim_{n \to \infty}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{\frac{d}{d n} \left(n + 1\right)^{3}}{\frac{d}{d n} n^{3}}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{\left(n + 1\right)^{2}}{n^{2}}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{\frac{d}{d n} 3 \left(n + 1\right)^{2}}{\frac{d}{d n} 3 n^{2}}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{6 n + 6}{6 n}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{\frac{d}{d n} \left(6 n + 6\right)}{\frac{d}{d n} 6 n}\right)$$
=
$$\lim_{n \to \infty} 1$$
=
$$\lim_{n \to \infty} 1$$
=
$$1$$
It can be seen that we have applied Lopital's rule (we have taken derivatives with respect to the numerator and denominator) 3 time(s)
The graph
Rapid solution [src]
1
$$1$$
Other limits n→0, -oo, +oo, 1
$$\lim_{n \to \infty}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right) = 1$$
$$\lim_{n \to 0^-}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right) = -\infty$$
More at n→0 from the left
$$\lim_{n \to 0^+}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right) = \infty$$
More at n→0 from the right
$$\lim_{n \to 1^-}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right) = 8$$
More at n→1 from the left
$$\lim_{n \to 1^+}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right) = 8$$
More at n→1 from the right
$$\lim_{n \to -\infty}\left(\frac{\left(n + 1\right)^{3}}{n^{3}}\right) = 1$$
More at n→-oo
The graph
Limit of the function (1+n)^3/n^3