6) ∫sin(1.5π + 0.5x) dx от π/4 до π
∫sin(1.5π + 0.5x) dx = -2cos(1.5π + 0.5x)
Подставляем верхний предел π: -2cos(1.5π + 0.5π) = -2cos(2π) = -2 * 1 = -2
Подставляем нижний предел π/4: -2cos(1.5π + 0.5π/4) = -2cos(6π/4 + π/8) = -2cos(13π/8)
-2 - (-2cos(13π/8)) = -2 + 2cos(13π/8)
Ответ: -2 + 2cos(13π/8)