$sin^2 15°+sin^2 20°+sin^2 25°+⋯+sin^2 75°=?$

$\tan \theta=p \text { হলে, } \cos 2 \theta=\text { কত? }$

$\tan 105^{\circ}=\tan \left(60^{\circ}+45^{\circ}\right)$ এর মান কত?

$\sin5\degree=r$হলে $2r\sqrt{1-r^2}\left(1-2r^2\right)$ কি নির্দেশ করে?

If $\displaystyle \cos \theta =\frac{5}{13}$, where $\theta$ being an acute angle, then the value of $\dfrac{\cos \theta +5\cot \theta }{\text {cosec}\ \theta -\cos \theta }$ will be