Functions Question 326

Question: The value of $ \underset{n\to \infty }{\mathop{\lim }},\frac{1+2+3+….n}{n^{2}+100} $ is equal

[Pb. CET 2002]

Options:

A) $ \infty $

B) $ \frac{1}{2} $

C) 2

D) 0

Show Answer

Answer:

Correct Answer: B

Solution:

We have, $ \underset{n\to \infty }{\mathop{\lim }},\frac{1+2+3+…..+n}{n^{2}+100} $ $ =\underset{n\to \infty }{\mathop{\lim }},\frac{n(n+1)}{2(n^{2}+100)}=\underset{n\to \infty }{\mathop{\lim }},\frac{n^{2}( 1+\frac{1}{n} )}{2n^{2}( 1+\frac{100}{n^{2}} )}=\frac{1}{2} $ .