ТРИГОНОМЕТРИЯ СРОЧНО!!!! sin((7π)/12)*cos((7π)/12)

Question

ТРИГОНОМЕТРИЯ
СРОЧНО!!!!
sin((7π)/12)*cos((7π)/12)

Answer 1

Sin (7П/12) * Cos (7П/12) = 1/2 * 2 *Sin(7П/12)Cos(7П712) = 1/2 Sin(7П/6) =
= 1/2 Sin(П + П/6) = - 1/2SinП/6 = - 1/2 * 1/2 = - 1/4 = - 0,25