If $x{\sin ^3}\alpha + y{\cos ^3}\alpha = \sin \alpha \cos \alpha $ and $x\sin \alpha - y\cos \alpha = 0,$ then ${x^2} + {y^2} = $
$-1$
$±1$
$1$
None of these
The angle subtended at the centre of a circle of radius $3$ metres by an arc of length $1$ metre is equal to
If $\cos x=-\frac{3}{5}, x$ lies in the third quadrant, find the values of other five trigonometric functions.
Find the value of the trigonometric function $\tan \frac{19 \pi}{3}$.
If $\cot \,\theta + \tan \theta = m$ and $\sec \theta - \cos \theta = n,$ then which of the following is correct
Find the degree measures corresponding to the following radian measures (Use $\pi=\frac{22}{7}$ ).
$-4$