Question

Prove that: sin θ - cos θ = 1 - 2 cos θ

LHS : sin θ - cos θ

        = (sin θ) - (cos θ)

        = (sin θ+cos θ) (sin θ - cos θ)...[using _____ ]

        = 1 [_____ - cos θ] ...[sin θ + cos θ = 1]

        = 1-_____

∴     LHS _____ RHS

∴     sin θ - cos θ = 1 - 2 cos θ​

Answer 1

I think your answer it clear