H
hientamkute


1. Rút gọn
a, A=[TEX](Sin \alpha+Cos \alpha)^2 -2.Sin \alpha.Cos \alpha -3 [/TEX]
b, B=[TEX](Sin \alpha-Cos \alpha)^2+2.Sin \alpha.Cos \alpha +2 [/TEX]
c, C=[TEX](Sin \alpha+Cos \alpha)^2 + (Sin \alpha-Cos \alpha)^2+5[/TEX]
a, A=[TEX](Sin \alpha+Cos \alpha)^2 -2.Sin \alpha.Cos \alpha -3 [/TEX]
b, B=[TEX](Sin \alpha-Cos \alpha)^2+2.Sin \alpha.Cos \alpha +2 [/TEX]
c, C=[TEX](Sin \alpha+Cos \alpha)^2 + (Sin \alpha-Cos \alpha)^2+5[/TEX]