MCQ
If $\tan \beta = \cos \theta \tan \alpha ,$ then ${\tan ^2}\frac{\theta }{2} = $
  • A
    $\frac{{\sin (\alpha + \beta )}}{{\sin (\alpha - \beta )}}$
  • B
    $\frac{{\cos (\alpha - \beta )}}{{\cos (\alpha + \beta )}}$
  • $\frac{{\sin (\alpha - \beta )}}{{\sin (\alpha + \beta )}}$
  • D
    $\frac{{\cos (\alpha + \beta )}}{{\cos (\alpha - \beta )}}$

Answer

Correct option: C.
$\frac{{\sin (\alpha - \beta )}}{{\sin (\alpha + \beta )}}$
c
(c) ${\tan ^2}\frac{\theta }{2} = \frac{{1 - \cos \theta }}{{1 + \cos \theta }} $

$= \frac{{\tan \alpha - \tan \beta }}{{\tan \alpha + \tan \beta }} $

$= \frac{{\sin (\alpha - \beta )}}{{\sin (\alpha + \beta )}}$.

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

Suppose four distinct positive numbers $a_1, a_2, a_3, a_4$ are in $G.P.$ Let $b_1=a_1, b_2=b_1+a_2, b_3=b_2+a_3$ and $b_4=b_3+a_4$.

$STATEMENT-1$ : The numbers $\mathrm{b}_1, \mathrm{~b}_2, \mathrm{~b}_3, \mathrm{~b}_4$ are neither in $A.P$. nor in $G.P.$ and 

$STATEMENT-2$ : The numbers $\mathrm{b}_1, \mathrm{~b}_2, \mathrm{~b}_3, \mathrm{~b}_4$ are in $H.P.$

Consider the following two statement. 

Statement $p$ : The value of $sin\,120^o$ can be divided by taking $\theta\, = 240^o$ in the equation $2\,\sin \frac{\theta }{2} = \sqrt {1 + \sin \theta }  - \sqrt {1 - \sin \theta } $ 

Statement $q$ : The angles $A, B, C$ and $D$ of any quadrilateral $ABCD$ satisfy the equation $\cos \left( {\frac{1}{2}\left( {A + C} \right)} \right) + \cos \left( {\frac{1}{2}\left( {B + D} \right)} \right) = 0$ 

Then the truth values of $p$ and $q$ are respectively.

The exponent of 3 in 100! is:
The length of the normal chord to the parabola ${y^2} = 4x$, which subtends right angle at the vertex is
The sum of all $3 -$digit numbers less than or equal to $500,$ that are formed without using the digit $"1"$ and they all are multiple of $11 ,$ is ..... .
If ${{({e^x} + 2)} \over {({e^x} - 1)\,(2{e^x} - 3)}} = - {3 \over {{e^x} - 1}} + {B \over {2{e^x} - 3}}$, then $B = $
If $\text{f(x)}=\cos(\log\text{x}),$ then value of $\text{f(x)}\text{f(4)}-\frac{1}{2}\Big\{\text{f}\Big(\frac{\text{x}}{4}\Big)+\text{f}(4\text{x})\Big\}$ is:
The product $(32),(32)^{\frac{1}{6}}(32)^{\frac{1}{36}}\ \dots\text{ to }\infty$ is equal to:
The value of $\sin \frac{\pi }{{16}}\sin \frac{{3\pi }}{{16}}\sin \frac{{5\pi }}{{16}}\sin \frac{{7\pi }}{{16}}$ is
The line joining the points $(-1, 3)$ and $(4, -2)$ will pass through the point $(p, q)$ if