The value of cot 15° cot 25° cot 45° cot 75° cot 65° is:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 1.
Concept used:
cotA.cotB = 1 when A + B = 90°
cot 45° = 1
Calculations:
⇒ cot 15° cot 25° cot 45° cot 75° cot 65°
Can be written as
⇒ cot 15° cot 75° cot 45° cot 25° cot 65°
⇒ 1