1 - 2 ^2 ( 4 + ) = - Vidyadip

MCQ

$1 - 2{\sin ^2}\left( {\frac{\pi }{4} + \theta } \right) = $

A
$\cos 2\theta $
B
$ - \cos 2\theta $
C
$\sin 2\theta $
✓
$ - \sin 2\theta $

✓

Answer

Correct option: D.

$ - \sin 2\theta $

d
(d) $1 - 2{\sin ^2}\left( {\frac{\pi }{4} + \theta } \right) $

$= \cos \left( {\frac{\pi }{2} + 2\theta } \right) $

$= - \sin 2\theta $.

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

Explore more

More "MCQ" from 3. trignometrical ratios,functions and identities→3. trignometrical ratios,functions and identities — all question types→MATHS STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

If the graph of $y = ax^3 + bx^2 + cx + d$ is symmetric about the line $x = k$ then

The diameter of a circle is $AB$ and $C$ is another point on circle, then the area of triangle $ABC$ will be

$\text{If}\ \sin2\theta+\sin2\phi=\frac{1}{2}\ \text{and}\ \cos2\theta\\ \ +\cos2\phi=\frac{3}{2},\text{then}\cos^2(\theta-\phi)=$

The point which divides the join of (1, 2) and (3, 4) externally in the ratio 1 : 1:

If $\mathop \sum \limits_{i = 1}^9 \left( {{x_i} - 5} \right) = 9$ and $\mathop \sum \limits_{i = 1}^9 {\left( {{x_i} - 5} \right)^2} = 45,$ then the standard deviation of the $9$ items ${x_1},{x_2},\;.\;.\;.\;,{x_9}$ is :

The three lines $lx + my + n = 0$, $mx + ny + l = 0$, $nx + ly + m = 0$ are concurrent if

The roots of the equation $a({x^2} + 1) - ({a^2} + 1)x = 0$ are

The length of the axes of the conic $9{x^2} + 4{y^2} - 6x + 4y + 1 = 0$, are

If the locus of the mid-point of the line segment from the point $(3,2)$ to a point on the circle, $x ^{2}+ y ^{2}=1$ is a circle of radius $r ,$ then $r$ is equal to ..... .

The number of terms with integral coefficient in the expansion of $\Big((27)^{\frac{1}{6}}+\sqrt[10]{32\text{x}}\Big)^{600}$ is: