Question

phân tích đa thức thành nhân tử

(x-y)²+4(x-y)-12

Answer 1

Bài làm:

Ta có: \(\left(x-y\right)^2+4\left(x-y\right)-12\)

\(=\left[\left(x-y\right)^2-4\left(x-y\right)+4\right]-16\)

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

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

\(=\left(x-y-6\right)\left(x-y+2\right)\)

Answer 2

\(\left(x-y\right)^2+4\left(x-y\right)-12\)

\(=\left(x-y\right)^2+2.2.\left(x-y\right)+4-16\)

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

\(=\left(x-y+6\right)\left(x-y-2\right)\)

Answer 3

Bài kia nhầm, làm lại:

\(\left(x-y\right)^2+4\left(x-y\right)-12\)

\(=\left[\left(x-y\right)^2+4\left(x-y\right)+4\right]-16\)

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

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

\(=\left(x-y-2\right)\left(x-y+6\right)\)

Answer 4

( x - y )² + 4( x - y ) - 12

= [ ( x - y )² + 2.2.( x - y ) + 4 ] - 16

= ( x - y + 2 )² - 4²

= ( x - y + 2 - 4 )( x - y + 2 + 4 )

= ( x - y - 2 )( x - y + 6 )

Answer 5

                                    Bài giải

\(\left(x-y\right)^2+4\left(x-y\right)-12\)

\(=[ \left(x-y\right)^2+4\left(x-y\right) +4\text{ }]-16\)

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

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

\(=\left(x-y-2\right)\left(x-y+6\right)\)