Use the information given about the angles and to find the exact value of:  

(a) sin(α + β)

(b) cos(α + β)

(c) sin(α - β)

(d) tan (α + β)

(e) sin(2α)

(f) cos (2β)

(g) sin β/2

(h) cosα/2

cscα = 2,  π/2 < α < π;     secβ = -3, π/2 < β < π