t² + 6t_z²+9

= t²+ 3×2×t _ z² + 3²

= ( t² + 3×2×t + 3²)_z²

= (t+3)²_ z²

= ((t + 3)_z)×((t+3)+z)

= ( t + 3 _z)×(t + 3 +z)

\(=3^2-z^2=\left(3-z\right)\left(3+z\right)\)

\(1,=x\left(x^2-2x+1-y^2\right)=x\left[\left(x-1\right)^2-y^2\right]=x\left(x-y-1\right)\left(x+y-1\right)\\ 2,=\left(x+y\right)^3\\ 3,=\left(2y-z\right)\left(4x+7y\right)\\ 4,=\left(x+2\right)^2\\ 5,Sửa:x\left(x-2\right)-x+2=0\\ \Leftrightarrow\left(x-2\right)\left(x-1\right)=0\Leftrightarrow\left[{}\begin{matrix}x=1\\x=2\end{matrix}\right.\)

A=   (\(x-y\))² - (y-z)²

A = (\(x-y\) - y + z)(\(x-y\) + y -  z)

A = ( \(x\) - 2y + z)(\(x-z\))

\(=\left(x-y\right)^2-z^2=\left(x-y-z\right)\left(x-y+z\right)\)

x^2 - 2xy + y^2 - z^2 

=(x-y)²-z²

=(x-y-z)(x-y+z)

\(x^2-2xy+y^2-z^2=\left(x-y\right)^2-z^2=\left(x-y+z\right)\left(x-y-z\right)\)

\(2\left(x-z\right)+xy-yz\)

\(=2\left(x-z\right)+y\left(z-z\right)\)

\(=\left(x-z\right)\left(2+y\right)\)

tham khảo:https://hoc247.net/hoi-dap/toan-8/phan-tich-da-thuc-x-2-y-2-3-z-2-x-2-3-y-2-z-2-3-thanh-nhan-tu-faq358831.html

Đây bạn nhé 

Bạn làm theo người này nhé, mik cũng khum bt. mik chỉ nhắc để bn có đáp án nhanh nhất thui