Question

What is the value of $\frac{\cos {80}^o}{\sin {10}^o}+\frac{\cos {59}^o}{\sin {31}^o}$ ?

• A. $2$
• B. $1$
• C. $0$
• D. $3$

Answer 1

The correct option is A $2$

$\frac{\cos 80°}{\sin 10°}+\frac{\cos 59°}{\sin 31°}$

$=\frac{\cos (90°-10°)}{\sin 10°}+\frac{\cos (90°-31°)}{\sin 31°}$

$=\frac{\sin 10°}{\sin 10°}+\frac{\sin 31°}{\sin 31°}$

$=1+1$

$=2$

Hence, the answer is $2.$