Question

cot(π/20).cot(3π/20).cot(5π/20).cot(7π/20).cot(9π/20)=1​

Answer 1

Answer:

Yahoo it it's the 7 and9 link

Answer 2

Answer:

Step-by-step explanation:

=Cotπ/20 cot3π/20 cot5π/20 cot7π/20 cot9π/20

=Cotπ/20 cot3π/20 cotπ/4 cot (π/2-3π/20) cot(π/2-π/20)

=Cotπ/20 cot3π/20 1 tan3π/20 tanπ/20

=1