Question

cot π/20cot3π/20cot5π/20cot7π/20cot9π/20=
​

Answer 1

Answer:

1

Step-by-step explanation:

cot π/20cot3π/20cot5π/20cot7π/20cot9π/20

= cot π/20 . cot 3π/20 . cot 5π/20 .

cot (π/2 - 3π/20) . cot (π/2 - π/20)

= cot π/20.cot 3π/20.cot5π/20.tan 3π/20.tan π/20

= cot 5π/20 ( since "cot & tan" are reciprocal to

each other)

= cot 45° ( since π = 180° )

= 1