Prove that sin(α + β).sin(α - β) = cos²(β) - cos²(α)

[@MuhammadSherazKhan-m6q]

🥰🥰🥰🥰🥰🥰🥰

[@rshahmaths]

Thanks dear

[@YousafKhan-l5z3s]

❤

[@rshahmaths]

Thanks

[@SanaUllah-q9s]

❤

[@rshahmaths]

Thanks

[@ziaullahshah0925]

❤

[@rshahmaths]

Thanks