Trigonometric F...

The value of \(\cos 20^{\circ}+\cos 100^{\circ}+\cos 140^{\circ}\) is:

If the value of \(\cos \theta+\sec \theta=\sqrt{3}\), find the value of \(\left(\cos ^{12} \theta+\right.\) \(\left.\tan ^{2} \theta\right):\left(\sec ^{6} \theta+\cos ^{6} \theta\right) ?\)

If \(\sin A \sin \left(60^{\circ}-A\right) \sin \left(60^{\circ}+A\right)=k \sin 3 A\), then find the value of \(k\) ?

If \(\sec ^{2} \theta+\tan ^{2} \theta=7\) then, find the value of \(\sec \theta\):

If \(\sin x+\cos x=\sqrt{2}\), then what is \(\cos ^{2}(2 x)\) equal to?

The equation \(\cos ^{2} \theta=\frac{(x+y)^{2}}{4 x y}\) is only possible when ?

The value of the \(\sin 1^{\circ}+\sin 2^{\circ}+\ldots+\sin 359^{\circ}\) is equal to:

Find the value of \(\cot \left(22 \frac{1}{2}^{\circ}\right)\).

\(\sin \theta+\sin 3 \theta+\sin 5 \theta+\operatorname{sin} 7 \theta\) is equal to:

If \(\sec ^{2} \theta+\tan ^{2} \theta=3\) then find the value of \(\cot \theta\).