MCQ
$\mathop {Limit}\limits_{x \to \infty } \,\frac{{{{\cot }^{ - 1}}\left( {\sqrt {x + 1} \,\, - \,\sqrt x } \right)}}{{{{\sec }^{ - 1}}\left\{ {{{\left( {\frac{{2x + 1}}{{x - 1}}} \right)}^x}} \right\}}}$ is equal to
  • $1$
  • B
    $0$
  • C
    $\pi /2$
  • D
    non existent

Answer

Correct option: A.
$1$
a
$\mathop {Limit}\limits_{x \to \infty } \,\sqrt {x + 1} \, - \sqrt x \,$ $= 0$  $\Rightarrow cot^{-1}(0) = \pi /2$
$\mathop {Limit}\limits_{x \to \infty } \,{\left( {\frac{{2x + 1}}{{x - 1}}} \right)^x}\,\, = \,\,\infty \,$ $\Rightarrow\,\,\, sec^{-1} (\infty ) = \pi /2$                     

$\therefore\,\, l = 1$ Ans 

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 area of the triangle formed by the positive $x$-axis and the normal and the tangent to the circle $x^2 + y^2 = 4$ at $(1, \sqrt 3 )$ is
If the sum of first $n$ terms of an $A.P.$ is $c n^2$, then the sum of squares of these $n$ terms is
The value of ${\log _2}.{\log _3}....{\log _{100}}{100^{{{99}^{{{98}^{{.^{{.^{{{.2}^1}}}}}}}}}}}$ is
The distance between the directrices of a rectangular hyperbola is $10$ units, then distance between its foci is
The equation of the circle which passes through the intersection of ${x^2} + {y^2} + 13x - 3y = 0$and $2{x^2} + 2{y^2} + 4x - 7y - 25 = 0$ and whose centre lies on $13x + 30y = 0$ is
Consider $\mathrm{L}_1: 2 \mathrm{x}+3 \mathrm{y}+\mathrm{p}-3=0$  ;  $\mathrm{L}_2: 2 \mathrm{x}+3 \mathrm{y}+\mathrm{p}+3=0$, where $p$ is a real number, and $C: x^2+y^2+6 x-10 y+30=0$.

$STATEMENT-1$ : If line $\mathrm{L}_1$ is a chord of circle $\mathrm{C}$, then line $\mathrm{L}_2$ is not always a diameter of circle $\mathrm{C}$.  and

$STATEMENT-2$ : If line $\mathrm{L}_1$ is a diameter of circle $\mathrm{C}$, then line $\mathrm{L}_2$ is not a chord of circle $\mathrm{C}$.

The locus of the mid-point of the distance between the axes of the variable line $x\cos \alpha + y\sin \alpha = p,$ where $p$ is constant, is
The number of values of $\alpha $ in $[0, 2\pi]$ for which $2\,{\sin ^3}\,\alpha  - 7\,{\sin ^2}\,\alpha  + 7\,\sin \,\alpha  = 2$ , is
If the circles $x^2+ y^2 = a$ and $x^2+ y^2 - 6x - 8y + 9 = 0$, touch externally, then $a =$
If $2\sin \theta + \tan \theta = 0$, then the general values of $\theta $ are