Question
$\mathop {\lim }\limits_{x \to 0} \frac{{\sqrt {1 + \sin x} - \sqrt {1 - \sin x} }}{x} = $

Answer

b
(b) $\frac{\sqrt{1+\sin x}+\sqrt{1-\sin x}}{\sqrt{1+\sin x}+\sqrt{1-\sin x}}$

Apply $L-$ Hospital‘s rule, 

$\mathop {\lim }\limits_{x \to 0} \frac{{\sqrt {1 + \sin x} - \sqrt {1 - \sin x} }}{x}$

$ = \mathop {\lim }\limits_{x \to 0} \,\,\frac{{\cos x}}{{2\sqrt {1 + \sin x} }} + \frac{{\cos x}}{{2\sqrt {1 - \sin x} }} = \frac{1}{2} + \frac{1}{2} = 1.$

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

If $\sin \theta + \cos \theta = 1$, then $\sin \theta \cos \theta = $
All the letters of the word $‘EAMCET’$ are arranged in all possible ways. The number of such arrangements in which two vowels are not adjacent to each other is
Suppose $A$ is any $3\times3$ non-singular matrix and $(A - 3I) (A- 5I)\, = 0$, where $I\,= I_3$ and $O\,= O_3$. If $\alpha A + \beta A^{- 1}\, = 4I$, then $\alpha + \beta $ is equal to
If $\lim \limits_{x \rightarrow 0}\left\{\frac{1}{x^{8}}\left(1-\cos \frac{x^{2}}{2}-\cos \frac{x^{2}}{4}+\cos \frac{x^{2}}{2} \cos \frac{x^{2}}{4}\right)\right\}=2^{-k}$ then the value of $k$ is
In the expansion of ${\left( {{x^2} - 2x} \right)^{10}}$, the coefficient of ${x^{16}}$ is
For each real number $x$, let $[ x ]$ denote the greatest integer less than or equal to $x$, and let $\{ x \}= x -[ x ]$. Then the smallest positive integer $M$ for which $\int_1^M\{x\}^{[x]} d x > 1$ is
Let $g(x) = 1 + x - [x]$ and $f(x) = \left\{ \begin{array}{l} - 1,\;x < 0\\0,\;\;x = 0,\;\\{\rm{1,}}\;\;\;{\rm{x}} > {\rm{0}}\end{array} \right.$ then for all $x,\;f(g(x))$ is equal to
Let $f, g:(0, \infty) \rightarrow R$ be two functions defined by $f(x)=\int_{-x}^x\left(|t|-t^2\right) e^{-t^2} d t$ and $g(x)=\int_0^{x^2} t^{1 / 2} e^{-t} d t$. Then the value of $\left(\mathrm{f}\left(\sqrt{\log _{\mathrm{e}} 9}\right)+\mathrm{g}\left(\sqrt{\log _{\mathrm{e}} 9}\right)\right)$ is
The number of elements in the set $S=$ $\left\{\theta \in[-4 \pi, 4 \pi]: 3 \cos ^{2} 2 \theta+6 \cos 2 \theta-\right.$ $\left.10 \cos ^{2} \theta+5=0\right\}$ is
If the coefficients of $x$ and $x^2$ in $(1+x)^p(1-x)^q$ are $4$ and $-5$ respectively, then $2 p+3 q$ is equal to