Question

Phân tích đa thức thành nhân tử

a)  xy + xz + 3y + 3z

b) x2 + 2x - 3

Answer 1

\(a,xy+xz+3y+3z=\left(xy+xz\right)+\left(3y+3z\right)=x\left(y+z\right)+3\left(y+z\right)=\left(y+z\right)\left(x+3\right)\\ b,x^2+2x-3=\left(x^2-x\right)+\left(3x-3\right)=x\left(x-1\right)+3\left(x-1\right)=\left(x-1\right)\left(x+3\right)\)

Answer 2

a,  xy+xz+3y+3z=(xy+xz) +(3y+3z)

=x. (y+z) +3.(y+z) 

=(x+3).(y+z) 

b, x^2+2x-3

= X^2+3x-x-3

=(x^2+3x)-(x+3)

=x. (x+3)-(x+3)

= (x-1).(x+3)

Answer 3

a, x(y+z) +3 (y+z)

= (x+3)(y+z)

b, x² +3x -x-3

= x(x+3) -(x+3)

= (x-1)(x+3)

Chúc em học tốt nha!