Question

Найти значение выражения 5*sin11П12*cos11П12

Answer 1

2sinx*cosx=sin2x

2.5*2sin11π/12*cos11π/12=2.5*sin11π/6=2.5*sin(10π/6+π/6)=
=-2.5sin π/6 = -2.5*1/2= -1.25