If cos (α + β) sin (γ + δ) = cos (α - β) sin (γ - δ), prove that cot α cot β cot γ = cot δ
Given,
cos (α + β) sin (γ + δ) = cos (α - β) sin (γ – δ)
Adding 1 both sides:
Now,
Subtracting 1 both sides:
Dividing equation (i) by equation (ii):
{sin (-A) = -sin A & cos (-A) = cos A}
⇒ cot α cot β cot γ = cot δ
Hence Proved