જો $tan\ 80^o = a$ અને $tan47^o = b$ હોય તો $tan37^o$ =
$\frac{{\alpha \, - \,\beta }}{{1\, + \,\alpha \beta }}$
$\frac{{\alpha \beta \, + \,1}}{{\alpha \, - \,\beta }}$
$\frac{{\alpha \beta \, - \,1}}{{\alpha \, + \,\beta }}$
$\frac{{\alpha \, + \,\beta }}{{1\, - \,\alpha \beta }}$
જો $\theta = 3\, \alpha$ અને $sin\, \theta =$ $\frac{a}{{\sqrt {{a^2}\,\, + \,\,{b^2}} }}$. થાય તો $a \,cosec\, \alpha - b \,sec\, \alpha$ ની કિમત ............. થાય
$cosec \frac{\pi }{{18}} - \sqrt 3 \,sec\, \frac{\pi }{{18}}$ =
કોઈ પણ $\theta \, \in \,\left( {\frac{\pi }{4},\frac{\pi }{2}} \right)$ માટે, $3\,{\left( {\sin \,\theta - \cos \,\theta } \right)^4} + 6{\left( {\sin \,\theta + \cos \,\theta } \right)^2} + 4\,{\sin ^6}\,\theta $ =
$2\,{\sin ^2}\beta + 4\,\,\cos \,(\alpha + \beta )\,\,\sin \,\alpha \,\sin \,\beta + \cos \,2\,(\alpha + \beta ) = $
સાબિત કરો કે : $\sin 2 x+2 \sin 4 x+\sin 6 x=4 \cos ^{2} x \sin 4 x$