(commence array l Rightarrow sin Acos C + sin Ccos A = 2cos Asin C Leftrightarrow sin Acos C = cos Asin C;(*)end array )T?t C?Tin H?c L?p 6Tin H?c L?p 7Tin H?c L?p 8Tin H?c L?p 9Tin H?c L?p 10Tin H?c L?p 11Tin H?c L?p twelveH? tr?i nghi?m, h??ng nghi?p eleven SGK Ho?t ??ng tr?i nghi?m, h??ng nghi?p - K?t n?i tri th?cH? tr?i nghi?m, h??ng nghi?p 3 S