If tan θ = 7/2 and cot ϕ = 5/8 , find the exact value of sin ( θ − ϕ ) .

Answer 1

1) Use Pythagoras (draw and label a diagram!) to determine sin θ, cos θ, sin φ, and cos φ.

2) Use sin (θ - φ) = sin θ cos φ - cos θ sin φ