Find the value of cot10° . cot19° . cot28° . cot37° . cot45° . cot53° . cot62°. cot71° . cot80° .
Answer & explanation
Correct answer: option 2
cot10° . cot19° . cot28° . cot37° . cot45° . cot53° . cot62°. cot71° . cot80°
Here, ⇒ (cot A . cot B = 1, when A + B = 90°)
So,
⇒ (cot10° . cot80°) . (cot19° . cot71°) . (cot28° . cot62°) . (cot37° . cot53°) . cot45°
= 1 × 1 × 1 × 1 × 1 = 1