Q. $\frac{\cos{9{^\circ} + \sin{9{^\circ}}}}{\cos{9{^\circ} - \sin{9{^\circ}}}}$ is equals to
A) $\tan{26{^\circ}}$
B) $\tan{81{^\circ}}$
C) $\tan{51{^\circ}}$
D) $\tan{54{^\circ}}$
Explanation
(d)
$\frac{\cos{9{^\circ} + \sin{9{^\circ}}}}{\cos{9{^\circ} - \sin{9{^\circ}}}} = \frac{1 + \tan{9{^\circ}}}{1 - \tan{9{^\circ}}}$
$= \tan{(45{^\circ} + 9{^\circ})}$
$= \tan{54{^\circ}}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.