Question

please answer this ASAP : If Cos α = 3/5 and sin β = - 9/41 and α is in the first Quadrant , β is in fourth Quadrant, find Sin(α + β), Sin(α - β), Cos(α + β), Cos(α - β), and determine in which quadrants α + β and α - β lie.

Answer 1

well draw 2 triangles 1st



so 1st quadrant sin and cos are positive

4th quadrant cos is positive sin is negative

then use the appropriate expansions...

Answer 2

oops