Using addition/subtraction identities, find an EXACT expression for sin (pi)/(12).
sin (pi / 12) =
sin (pi/3 - pi/4) =
sin(pi/3)cos(pi/4) - sin(pi/4)cos(pi/3) =
(√3/2)(1/√2) - (1/√2)(1/2) =
[ (√3 - 1) / 2(√2) ]
