The value of cot5°. cot15°. cot25°. cot45°. cot65°. cot75°. cot85° is:
Answer & explanation
Correct answer: option 1
⇒ cot5°. cot15°. cot25°. cot45°. cot65°. cot75°. cot85°
= (cot 5° cot 85°) (cot 15° cot 75°) (cot 25° cot 65°) cot 45°
[ cot A.cot B = 1, when A + B = 90°]
= 1 × 1 × 1 × cot45° = 1