Refer to the diagram shown below.
In quadrant 1, the angle changes from 0 to π/2 radians.
In quadrant 2, the angle changes from π/2 to π radians.
In quadrant 3, the angle changes from π to (3/2)π radians.
In quadrant 4, the angle changes from (3/2)π to 2π radians.
Note that angles are measured counterclockwise from the positive x-axis.
Because (11/6)π lies between π and (3/2)π, the angle is in the quadrant 3.