Question

prove that 2sin5π/12sinπ/12=1/2​

Answer 1

LHS = 2 sin 5π / 12

12 sin π / 12

= 2 sin ( 5 * 15 )

12 sin ( 15 )

=. 2 sin ( 75° ) / 12 sin ( 15° )

2 * ( √3 + 1 )

=. 2√2

12 * ( √3 - 1 )

2√2

= 1 / 2

= RHS