Выражение: sin(19п/2+x)+cos(7п-x)+cos(7п/2-x)+sin(5п-x)

Sin(19π/2 + x) = sin(10π - π/2 + x) = -sin(π/2 - x) = -cosx
cos(7π - x) = cos(π - x) = -cosx
cos(7π/2 - x) = cos(4π - π/2 - x) = cos(π/2 + x) = -sinx
sin(5π - x) = sin(π - x) = sinx
-cosx - cosx - sinx + sinx = -2cosx