\(x^2y+xy^2+x^2z+y^2z+2xyz\)
\(=x^2z+2xyz+y^2z+x^2y+xy^2\)
\(=\left(x^2z+2xyz+y^2z\right)+\left(x^2y+xy^2\right)\)
\(=z.\left(x^2+2xy+y^2\right)+xy.\left(x+y\right)\)
\(=z.\left(x+y\right)^2+xy.\left(x+y\right)\)
\(=\left(x+y\right).\left[z.\left(x+y\right)+xy\right]\)
\(=\left(x+y\right).\left(xz+yz+xy\right)\)
Chúc bạn học tốt!