cos(П/2 + а) + sin(П + а)
cos(П/2)cos(a) - sin(П/2)sin(a) + sin(П)cos(a) + cos(П)sin(a)
0 cos(a) - 1 sin(a) + 0 cos(a) + (-1) sin(a)
-2sin(a)
Ответ: -2sin(a)
cos(П/2 + а) + sin(П + а)
cos(П/2)cos(a) - sin(П/2)sin(a) + sin(П)cos(a) + cos(П)sin(a)
0 cos(a) - 1 sin(a) + 0 cos(a) + (-1) sin(a)
sin(a) - sin(a)-2sin(a)
Ответ: -2sin(a)