Question

9x²y²-18xy+9  trình bày

Answer 1

\(9x^2y^2-18xy+9\)

\(=9\left(x^2y^2-2xy+1\right)\)

\(=9\left[\left(xy\right)^2-2xy+1\right]\)

\(=9\left(xy-1\right)^2\)

Answer 2

\(=9\left(x^2y^2-2xy+1\right)=9\left(xy-1\right)^2\)

Answer 3

\(9x^2y^2-18xy+9\\ =9\left(x^2y^2-2xy+1\right)\\ =9\left[\left(xy\right)^2-2xy.1^2+1\right]\\ =9\left(xy-1\right)^2\)