Question

$\frac{\sin 91^{\circ}+\sin 1^{\circ}}{\sin 91^{\circ}-\sin 1^{\circ}}=$

• A. $\tan 46^{\circ}$
• B. $\cot 46^{\circ}$
• C. $\sin 46^{\circ}$
• D. $\cos 46^{\circ}$
• E. $1$

Answer 1

Answer: (A)

$\frac{\sin 91+\sin 1}{\sin 91-\sin 1}=\frac{\cos 1+\sin 1}{\cos 1-\sin 1}$
$=\frac{1+\tan 1}{1-\tan 1}$
$=\tan (45+1)$
$=\tan 46^{\circ}$