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(11+4*(1+n)^2+8*n)/(3+4*n^2+8*n)

Limit of the function (11+4*(1+n)^2+8*n)/(3+4*n^2+8*n)

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     /              2      \
     |11 + 4*(1 + n)  + 8*n|
 lim |---------------------|
n->oo|           2         |
     \    3 + 4*n  + 8*n   /
$$\lim_{n \to \infty}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right)$$
Limit((11 + 4*(1 + n)^2 + 8*n)/(3 + 4*n^2 + 8*n), n, oo, dir='-')
Detail solution
Let's take the limit
$$\lim_{n \to \infty}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right)$$
Let's divide numerator and denominator by n^2:
$$\lim_{n \to \infty}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right)$$ =
$$\lim_{n \to \infty}\left(\frac{4 + \frac{16}{n} + \frac{15}{n^{2}}}{4 + \frac{8}{n} + \frac{3}{n^{2}}}\right)$$
Do Replacement
$$u = \frac{1}{n}$$
then
$$\lim_{n \to \infty}\left(\frac{4 + \frac{16}{n} + \frac{15}{n^{2}}}{4 + \frac{8}{n} + \frac{3}{n^{2}}}\right) = \lim_{u \to 0^+}\left(\frac{15 u^{2} + 16 u + 4}{3 u^{2} + 8 u + 4}\right)$$
=
$$\frac{15 \cdot 0^{2} + 0 \cdot 16 + 4}{3 \cdot 0^{2} + 0 \cdot 8 + 4} = 1$$

The final answer:
$$\lim_{n \to \infty}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right) = 1$$
Lopital's rule
We have indeterminateness of type
oo/oo,

i.e. limit for the numerator is
$$\lim_{n \to \infty}\left(8 n + 4 \left(n + 1\right)^{2} + 11\right) = \infty$$
and limit for the denominator is
$$\lim_{n \to \infty}\left(4 n^{2} + 8 n + 3\right) = \infty$$
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
$$\lim_{n \to \infty}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right)$$
=
Let's transform the function under the limit a few
$$\lim_{n \to \infty}\left(\frac{8 n + 4 \left(n + 1\right)^{2} + 11}{4 n^{2} + 8 n + 3}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{\frac{d}{d n} \left(8 n + 4 \left(n + 1\right)^{2} + 11\right)}{\frac{d}{d n} \left(4 n^{2} + 8 n + 3\right)}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{8 n + 16}{8 n + 8}\right)$$
=
$$\lim_{n \to \infty}\left(\frac{\frac{d}{d n} \left(8 n + 16\right)}{\frac{d}{d n} \left(8 n + 8\right)}\right)$$
=
$$\lim_{n \to \infty} 1$$
=
$$\lim_{n \to \infty} 1$$
=
$$1$$
It can be seen that we have applied Lopital's rule (we have taken derivatives with respect to the numerator and denominator) 2 time(s)
The graph
Rapid solution [src]
1
$$1$$
Other limits n→0, -oo, +oo, 1
$$\lim_{n \to \infty}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right) = 1$$
$$\lim_{n \to 0^-}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right) = 5$$
More at n→0 from the left
$$\lim_{n \to 0^+}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right) = 5$$
More at n→0 from the right
$$\lim_{n \to 1^-}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right) = \frac{7}{3}$$
More at n→1 from the left
$$\lim_{n \to 1^+}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right) = \frac{7}{3}$$
More at n→1 from the right
$$\lim_{n \to -\infty}\left(\frac{8 n + \left(4 \left(n + 1\right)^{2} + 11\right)}{8 n + \left(4 n^{2} + 3\right)}\right) = 1$$
More at n→-oo
The graph
Limit of the function (11+4*(1+n)^2+8*n)/(3+4*n^2+8*n)