Ответы и объяснения

2012-06-06T07:51:30+00:00

1/2 · π/3 - 2· π/3 =  π/6 -  2π/3 = - 3π/6 =  - π/2

Sin(2π/3 + 3π/3) = Sin π/3 = √3/2    

  

2012-06-06T08:00:35+00:00

1) (1/2)*(pi/3) - 2* (2pi/3) = (pi/6) - (4pi/3) = (pi - 8pi)/6 = - 7pi/6

2)  sin(2*(pi/3) + 3*(pi/3)) = sin(5pi/3) = sin(2pi - (pi/3)) = - sin(pi/3) = - (sqrt3)/2