Nguyễn Minh Tuấn's Profile

1. a,x²-2xy+y²=(x-y)²

^​b,x²-y²=(x-y)(x+y)

c,x²+2x+1=x²+2x1+1²=(x+1)²

d,x³-3x²+3x-1=(x³-x²)-(2x²-2x)+(x-1)=(x²-2x+1)(x-1)=(x-1)²(x-1)=(x-1)³

e,x³+27=x³+3³=(x+3)(x²-3x+9)

3 phân tử CaCO3 là gì