MCQ
${d \over {dx}}\sqrt {{{1 - \sin 2x} \over {1 + \sin 2x}}} = $
  • A
    ${\sec ^2}x$
  • $ - {\sec ^2}\left( {{\pi \over 4} - x} \right)$
  • C
    ${\sec ^2}\left( {{\pi \over 4} + x} \right)$
  • D
    ${\sec ^2}\left( {{\pi \over 4} - x} \right)$

Answer

Correct option: B.
$ - {\sec ^2}\left( {{\pi \over 4} - x} \right)$
b
(b) $y = \sqrt {\frac{{1 - \sin 2x}}{{1 + \sin 2x}}} = \frac{{\cos x - \sin x}}{{\cos x + \sin x}}$

$ = \frac{{1 - \tan x}}{{1 + \tan x}} = \tan \left( {\frac{\pi }{4} - x} \right) $

$\Rightarrow \frac{{dy}}{{dx}} = - {\sec ^2}\left( {\frac{\pi }{4} - x} \right)$.

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

Consider the following statements on a set $A=\{1,2,3\}$ :
(i) $\quad R=\{(1,1),(2,2)\}$ is a reflexive relation on $A$.
(ii) $R=\{(3,3)\}$ is symmetric and transitive but not a reflexive relation on $A$.
Which of the statements given above is/are correct?
Choose the correct answer from the given four options.

A box contains 3 orange balls, 3 green balls and 2 blue balls. Three balls are drawn at random from the box without replacement. The probability of drawing 2 green balls and one blue ball is:

  1. $\frac{3}{28}$

  2. $\frac{2}{21}$

  3. $\frac{1}{28}$

  4. $\frac{167}{168}$

The correct evaluation of $\int_0^\pi {\left| {\,{{\sin }^4}x\,} \right|\,dx} $ is
Let $X$ and $Y$ be subsets of $R$, the set of all real numbers. The function $f:X \to Y$ defined by $f(x) = {x^2}$ for $x \in X$ is one-one but not onto if (Here ${R^ + }$ is the set of all positive real numbers)
The area of region $\{ \,(x,\,y):{x^2} + {y^2} \le 1 \le x + y\} $ is
Let A = {2, 3, 4, 5, ..., 17, 18}. Let $'\simeq'$ be the equivalence relation on A × A, cartesian product of A with itself, defined by $(\text{a, b})\simeq(\text{c, d)}$ if ad = bc. Then, the number of ordered pairs of the equivalence class of (3, 2) is:
  1. 4
  2. 5
  3. 6
  4. 7
If $\alpha \in (2 , 3) $ then number of solution of the equation $\int\limits_0^\alpha  {}  \cos (x + \alpha^2)\, dx = \sin \,\alpha$ is :
If the function $\text{f}(\text{x})=\frac{-\text{x}}{2}+\sin\text{x}$ defined on $\Big[\frac{-\pi}{3},\frac{\pi}{3}\Big]$ is:
  1. Increasing.
  2. Decreasing.
  3. Constant.
  4. None of these.
Number of solutions of the equation $2e^{|x|}tan^{-1}|x|=1$ is -
If $\omega $is a cube root of unity, then $\left| {\,\begin{array}{*{20}{c}}{x + 1}&\omega &{{\omega ^2}}\\\omega &{x + {\omega ^2}}&1\\{{\omega ^2}}&1&{x + \omega }\end{array}\,} \right| = $