Question

phân tích đa thức thành nhân tử:

2xy−x^2−y^2+16

 

Answer 1

\(2xy-x^2-y^2+16\)

\(=-\left(x^2-2xy+y^2-16\right)\)

\(=-\left[\left(x^2-2xy+y^2\right)-4^2\right]\)

\(=-\left[\left(x-y\right)^2-4^2\right]\)

\(=-\left[\left(x-y-4\right)\left(x-y+4\right)\right]\)

\(=-\left(x-y-4\right)\left(x-y+4\right)\)

Answer 2

\(=16-\left(x^2-2xy+y^2\right)\)

\(=4^2-\left(x-y\right)^2\)

\(=\left(4-x+y\right)\left(4+x-y\right)\)