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(-5+7*n)/(2+n)

Limit of the function (-5+7*n)/(2+n)

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     /-5 + 7*n\
 lim |--------|
n->oo\ 2 + n  /
limn(7n5n+2)\lim_{n \to \infty}\left(\frac{7 n - 5}{n + 2}\right)
Limit((-5 + 7*n)/(2 + n), n, oo, dir='-')
Detail solution
Let's take the limit
limn(7n5n+2)\lim_{n \to \infty}\left(\frac{7 n - 5}{n + 2}\right)
Let's divide numerator and denominator by n:
limn(7n5n+2)\lim_{n \to \infty}\left(\frac{7 n - 5}{n + 2}\right) =
limn(75n1+2n)\lim_{n \to \infty}\left(\frac{7 - \frac{5}{n}}{1 + \frac{2}{n}}\right)
Do Replacement
u=1nu = \frac{1}{n}
then
limn(75n1+2n)=limu0+(75u2u+1)\lim_{n \to \infty}\left(\frac{7 - \frac{5}{n}}{1 + \frac{2}{n}}\right) = \lim_{u \to 0^+}\left(\frac{7 - 5 u}{2 u + 1}\right)
=
7002+1=7\frac{7 - 0}{0 \cdot 2 + 1} = 7

The final answer:
limn(7n5n+2)=7\lim_{n \to \infty}\left(\frac{7 n - 5}{n + 2}\right) = 7
Lopital's rule
We have indeterminateness of type
oo/oo,

i.e. limit for the numerator is
limn(7n5)=\lim_{n \to \infty}\left(7 n - 5\right) = \infty
and limit for the denominator is
limn(n+2)=\lim_{n \to \infty}\left(n + 2\right) = \infty
Let's take derivatives of the numerator and denominator until we eliminate indeterninateness.
limn(7n5n+2)\lim_{n \to \infty}\left(\frac{7 n - 5}{n + 2}\right)
=
limn(ddn(7n5)ddn(n+2))\lim_{n \to \infty}\left(\frac{\frac{d}{d n} \left(7 n - 5\right)}{\frac{d}{d n} \left(n + 2\right)}\right)
=
limn7\lim_{n \to \infty} 7
=
limn7\lim_{n \to \infty} 7
=
77
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
02468-8-6-4-2-1010-500500
Other limits n→0, -oo, +oo, 1
limn(7n5n+2)=7\lim_{n \to \infty}\left(\frac{7 n - 5}{n + 2}\right) = 7
limn0(7n5n+2)=52\lim_{n \to 0^-}\left(\frac{7 n - 5}{n + 2}\right) = - \frac{5}{2}
More at n→0 from the left
limn0+(7n5n+2)=52\lim_{n \to 0^+}\left(\frac{7 n - 5}{n + 2}\right) = - \frac{5}{2}
More at n→0 from the right
limn1(7n5n+2)=23\lim_{n \to 1^-}\left(\frac{7 n - 5}{n + 2}\right) = \frac{2}{3}
More at n→1 from the left
limn1+(7n5n+2)=23\lim_{n \to 1^+}\left(\frac{7 n - 5}{n + 2}\right) = \frac{2}{3}
More at n→1 from the right
limn(7n5n+2)=7\lim_{n \to -\infty}\left(\frac{7 n - 5}{n + 2}\right) = 7
More at n→-oo
Rapid solution [src]
7
77
The graph
Limit of the function (-5+7*n)/(2+n)