Question

Cot 9 degree cot 27 degree cot 45 degree cot 63 degree cot 81 = 1

Answer 1

Step-by-step explanation:

cot9•cot27•cot45•cot63•tan(90-9)

cot9•cot27•cot45•tan(90-27)•tan9

cot9•cot27•cot45•tan27•tan9

1. now cot45=1 and cot9•tan9=1,cot27•tan27=1

hence LHS=RHS

HOPE THIS WILL HELP U