Question
Evaluate the following limit:
$\lim\limits_{\text{x}\rightarrow{1}}\frac{1-\frac{1}{\text{x}}}{\sin\pi(\text{x}-1)}$

Answer

$\lim\limits_{\text{x}\rightarrow{1}}\frac{1-\frac{1}{\text{x}}}{\sin\pi(\text{x}-1)}$
As x → 1, then x - 1 → 0 let x - 1 = y
$=\lim\limits_{{\text{x}-{1\rightarrow0}}}\frac{(\text{x}-1)}{\text{x}\times\sin\pi(\text{x}-1)}$
$=\lim\limits_{{\text{y}\rightarrow0}}\frac{\text{y}}{(\text{y}+1)\sin(\pi\text{y})}$
$=\lim\limits_{{\text{y}\rightarrow0}}\frac{\text{y}}{(\text{y}+1)\sin(\pi\text{y})}$
$=\lim\limits_{{\text{y}\rightarrow0}}\frac{1}{\frac{(\text{y}+1)\sin(\pi\text{y})}{\text{y}}}$
$=\frac{1}{\Big(\lim\limits_{\text{y}\rightarrow0}(\text{y}+1)\Big)\times\Big(\lim\limits_{\text{y}\rightarrow0}\frac{\sin\pi\text{y}}{\text{y}\times\pi}\times\pi\Big)}$
$=\frac{1}{(1)(1\times\pi)}$ $\Big[\because\lim\limits_{\theta\rightarrow0}\frac{\sin\theta}{\theta}=1\Big]$
$=\frac{1}{\pi}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

The age distribution of 100 life-insuance policy holders is an follows:
Age (on nearest birth day)
17-19.5
20-25.5
26-35.5
36-40.5
41-50.5
51-55.5
56-60.5
61-70.5
No. of persons
5
16
12
26
14
12
6
5
There are three social media groups on a mobile: Group I, Group II and Group III. The

probabilities that Group I, Group II and Group III sending the messages on sports are $\frac{2}{5}, \frac{1}{2}$

and $\frac{2}{3}$ respectively. The probability of opening the messages by Group I, Group II and

Group III are $\frac{1}{2}, \frac{1}{4}$ and $\frac{1}{4}$ respectively. Randomly one of the messages is opened and

found a message on sports. What is the probability that the message was from Group III.

Prove that
$\cos\frac{\pi}{65}\cos\frac{2\pi}{65}\cos\frac{4\pi}{65}\cos\frac{8\pi}{65}\cos\frac{16\pi}{65}\cos\frac{32\pi}{65}=\frac{1}{64}$
Find $m$ and $n$, if ${ }^{(m+n)} P_2=56$ and ${ }^{(m-n)} P_2=12$.
Let $f(x) = x^2 $ and $g(x) = 2x + 1$ be two real functions. Find $(f + g)(x), (f - g)(x), (fg)(x)$ and $\Big(\frac{\text{f}}{\text{g}}\Big)\text{x}$
The towers of a bridge, hung in the form of a parabola, have their tops 30 metres above the roadway and are 200 metres apart. If the cable is 5 metres above the roadway at the centre of the bridge, find the length of the vertical supporting cable 30 metres from the centre.
If $\cos\text{x}-\sin\text{x}=\text{a}^3, \sec\text{x}-\cos\text{x}=\text{b}^3,$ than proved that $a^2b^2 (a^2 + b^2) = 1.$
Prove that the centres of the three circles $x^2+ y^2 - 4x - 6y - 12 = 0 , x^2 + y^2 + 2x + 4y - 10 = 0$ and $x^2 + y^2 - 10x - 16y - 1 = 0$ are collinear.
The variance of 20 observation is 5. If each observation is multiplied by 2, find the variance of the resulting observation.
Which of the following functions has a removable discontinuity?
$\begin{array}{rlr}
f(x)=\frac{x^3-8}{x^2-4}, & & \text { for } x >2 \\
=3, & \text { for } x=2 \\
=\frac{e^{3(x-2)^2}-1}{2(x-2)^2}, & \text { for } x<2
\end{array}
$