69
The equality $\sin A+\sin 2 A+\sin 3 A=3$ holds for some real value of $A$.
A
TRUE
B
FALSE
70
$\sin10\Upsilon$ is greater than $\cos10\Upsilon$.
A
TRUE
B
FALSE
71
$\cos \frac{2 \pi}{15} \cos \frac{4 \pi}{15} \cos \frac{8 \pi}{15} \cos \frac{16 \pi}{15}=\frac{1}{16}$
A
TRUE
B
FALSE
72
One value of $\theta$ which satisfies the equation $\sin^4\theta-2\sin^2\theta-1$ lies between $\theta$ and $2\pi$.
A
TRUE
B
FALSE
73
If $\operatorname{cosec} x=1+\cot x$, then $x=2 n \pi, 2 n \pi+\frac{\pi}{2}$
A
TRUE
B
FALSE