Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
BITSAT 2015
Exam
BITSAT
Year
2015
Subject
Mathematics
Chapter
Limits

BITSAT 2015 · Mathematics · Limits

If _ x arrow x ((1)/(x))=A and _ x arrow 0 x ((1)/(x))=B , then...

If lim⁡x→xsin⁡(1x)=Aand\lim _{x \rightarrow} x \sin \left(\frac{1}{x}\right)=A and\lim _{x \rightarrow 0} x \sin \left(\frac{1}{x}\right)=B$, then which one of the following is correct?

Options

  1. AA=1A=1 and B=0B=0
  2. BA=0\quad A=0 and B=1B=1
  3. CA=0A=0 and B=0B=0
  4. DA=1A=1 and B=1B=1

Correct answer

A. A=1A=1 and B=0B=0

Step-by-step solution

As given, A=lim⁡x→∞xsin⁡\mathrm{A}=\lim _{\mathrm{x} \rightarrow \infty} \mathrm{x} \sin\left(\frac{1}{\mathrm{x}}\right)=\lim _{\mathrm{x} \rightarrow \infty} \frac{\sin \left(\frac{1}{\mathrm{x}}\right)}{\left(\frac{1}{\mathrm{x}}\right)}LetLet\mathrm{t}=\frac{1}{\mathrm{x}}whenwhen\mathrm{x} \rightarrow \alpha, \mathrm{t} \rightarrow 0 ⇒A=lim⁡t→∞sin⁡tt=1 and [∵lim⁡t→0sin⁡xx=1]\begin{aligned} \Rightarrow\mathrm{A}&=\lim _{t \rightarrow \infty} \frac{\sin \mathrm{t}}{\mathrm{t}}=1 \\ \text{ and } \left[\because \lim _{\mathrm{t} \rightarrow 0} \frac{\sin \mathrm{x}}{\mathrm{x}}=1\right] \end{aligned} and \mathrm{B}=\lim _{\mathrm{x} \rightarrow 0} \mathrm{x} \sin \left(\frac{1}{\mathrm{x}}\right) \Rightarrow \mathrm{B}=\lim _{\mathrm{x} \rightarrow 0} \mathrm{x} \cdot \lim _{\mathrm{x} \rightarrow 0} \sin \left(\frac{1}{\mathrm{x}}\right) \Rightarrow \mathrm{B}=0∴A=1andB=0\therefore \quad A=1 and B=0 is correct
Practice Limits on Quantrex Academy →

More from Limits

Given a real valued function ' f ' such that f(x)=\ array cc ^2\ x\ x^2-[x]^2 & for x>0 1… BITSAT 2024Let f(x)= x, g(x)= x, h(x)=x^2 then _ x arrow 1 (f(g(h(x)))-f(g(h(1))))/(x-1)= BITSAT 2024If f(x)=\ array l x^2-1,0 < x < 2 2 x+3,2 ≤ x < 3 array . , then the quadratic equation… BITSAT 2023_ x arrow 0 (| x|)/(x) is equal to BITSAT 2023The value of _ x arrow 0 (1- (1- x))/(x^4) is BITSAT 2022The value of _ x arrow 0 (1+x)^ (1)/(x) -e+(1)/(2) e x x^2 is BITSAT 2022Value of _ x arrow 0 a^ x -1 x is BITSAT 2021_ x arrow 0 2 ^ 2 3 x x^ 2 is equal to BITSAT 2021_ x arrow 0 x- x x+ ^ 2 x is equal to BITSAT 2021The value of _ x → (3π)/(4) 4 ^ 2 xcosx - x + x x + x is BITSAT 2019The value of a , so that _ x → 0 (1)/(x2)(e^ ax - e^ x - x) = (3)/(2) ,& is BITSAT 2018_ n → ∞ sin [π n^ 2 + 1 ] is equal to BITSAT 2017If _ n → ∞ (an - 1 + n^ 2 1 + n ) = b , where a is finite number, then BITSAT 2017_ n arrow ∞ a^ n +b^ n a^ n -b^ n , where a > b > 1, is equal to BITSAT 2016_ x arrow ∞ ∫_ 0 ^ 2 x x e^ x^ 2 d x e^ 4 x^ 2 equals BITSAT 2015_ x arrow 0 (cosec x)^ 1 / x is equal to : BITSAT 2014 Full Limits list Limits JEE Maths PYQsJEE Mathematics PYQs All BITSAT PYQs