How can sin(7π/12 ) can be evaluated using compound angle formulas in two different ways?

Answer 1

sin(2 * 7π/6)
cos(π/2 - 7π/12) = cos(1/2 * π/6)

Answer 2

and of course the obvious one:

sin(7π/12 )
= sin(π/3 + π/4)
= sin π/3 cos π/4 + cos π/3 sin π/4
= (√3/2)(√2/2) + (1/2)(√2/2)
= (√6 + √2)/4