sec = 1/cos csc = 1/sin so we need sin and cos for all of the objects
5pi/6 sin = 1/2 cos = - sqrt3/2
5pi/4 sin = - sqrt2/2 cos = -srt2/2
11pi/6 sin = -1/2 cos = sgrt3/2
so ....adding all of these inverses
2 - 2 /sqrt3 - 2/sqrt2 - 2/sqrt2 - 2 + 2/sqrt3 = - 4 / sqrt 2 = - 4 sqrt 2/2 = - 2 sqrt 2