C
casaultk


1/tính:
[TEX]sin5^o.sin15^o......sin75^o.sin85^o[/TEX]
2/ rút gọn: [TEX]A=cos^3asina- sin^3acosa[/TEX]
[TEX]sin5^o.sin15^o......sin75^o.sin85^o[/TEX]
2/ rút gọn: [TEX]A=cos^3asina- sin^3acosa[/TEX]
Last edited by a moderator: