Question

Phân tích các đa thức sau thành nhân tử

a) x^2-3xy+2x-6y

b) x^2+y^2+2xy-4

c)x^2-3x+2

d)2xy+3zy+6y+xz

Answer 1

a/\(\left(x^2-3xy+\frac{9}{4}y^2+2x-\frac{9}{2}y+1\right)+\left(-\frac{9}{4}y^2+\frac{9}{2}y-1\right)=\left(x-\frac{3}{2}y+1\right)^2-\left(\frac{3}{2}y-1\right)^2=\left(x-\frac{3}{2}y+1-\frac{3}{2}y+1\right)\left(x-\frac{3}{2}y+1+\frac{3}{2}-1\right)=\left(x-3y+2\right)x\)b/\(=\left(x-y\right)^2-4=\left(x-y-2\right)\left(x-y+2\right)\)

c/\(=x^2-x-2x+2=x\left(x-1\right)-2\left(x-1\right)=\left(x-2\right)\left(x-1\right)\)