If cosα + cosβ = A and sinα + sinβ = B, find sin(α – β)
If cosα + cosβ = A and sinα + sinβ = B, find sin(α – β).
(a) A2+B2-2/2
(b) A2+B2+2/2
(c) A² – B² + 1
(d) A² + B² – 4
Sol:
Put α = β = 0
A = 2
B = 0
Sin0 = 0
Only option D satisfies
(4) + 0 – 4 = 0