Question

[Phan Duong Quynh Anh]

Phan tich da thuc thanh nhan tu :

a) x^2 - x - y^2 - y

b) x^2 - 2 xy + y^2 - z^2

c) 5x - 5y + ax - ay 

d) a^3 - a^2 x - ay + xy

e) 4x^2 - y^2 +4x + 1

Answer 1

[Nguyễn Gia Triệu]

a) x²-x-y²-y=(x²-y²)-(x+y)=(x+y)(x-y)-(x+y)=(x+y)(x-y-1)

b)x²-2xy+y²-z²=(x-y)²-z²=(x-y-z)(x-y+z)

c)5x-5y+ax-ay=5(x-y)+a(x-y)=(x-y)(5+a)

d)a³-a²x-ay+xy=a²(a-x)-y(a-x)=(a-x)(a²-y)

e)4x²-y²+4x+1=[(2x)²+2.2x.1+1²]-y²=(2x+1)²-y²=(2x+1-y)(2x+1+y)

Chúc bạn học tốt!