કિંમત શોધો : $\sin 75^{\circ}$
$\sin 75^{\circ}=\sin \left(45^{\circ}+30^{\circ}\right)$
$=\sin 45^{\circ} \cos 30^{\circ}+\cos 45^{\circ} \sin 30^{\circ}$
$[\sin (x+y)=\sin x \cos y+\cos x \sin y]$
$=\left(\frac{1}{\sqrt{2}}\right)\left(\frac{\sqrt{3}}{2}\right)+\left(\frac{1}{\sqrt{2}}\right)\left(\frac{1}{2}\right)$
$=\frac{\sqrt{3}}{2 \sqrt{2}}+\frac{1}{2 \sqrt{2}}=\frac{\sqrt{3}+1}{2 \sqrt{2}}$
સાબિત કરો કે : $\frac{(\sin 7 x+\sin 5 x)+(\sin 9 x+\sin 3 x)}{(\cos 7 x+\cos 5 x)+(\cos 9 x+\cos 3 x)}=\tan 6 x$
અંશ માપ શોધો. ( $\pi=\frac{22}{7}$ લો. ) $\frac{11}{16}$
જો $\sin \theta + {\rm{cosec}}\theta = {\rm{2}}$, તો ${\sin ^2}\theta + {\rm{cose}}{{\rm{c}}^{\rm{2}}}\theta = $
$\cos A - \sin A$ જયારે $A = \frac{{5\pi }}{4}, = . . . . $