Evaluate the given function with the following information: sin α = 4/5 (α in the first quadrant) and cos β = -12/13 (β in the second quadrant). cos( α + β)
Evaluate the given function with the following information: sin α = 4/5 (α in the first quadrant) and cos β =
-12/13 (β in the second quadrant).
cos( α + β)