Question

2x的2次方y-8xy+8y 怎么分解因式？

2x的2次方y-8xy+8y

a^2(x-y)-4b^2(x-y)
2009^2-2008×2010
999^2+999×2+1
121×0.13+12.1×0.9-12×1.21

Answer 1

2x的2次方y-8xy+8y
=2y(x^2-4x+4)
=2y(x-2)^2

a^2(x-y)-4b^2(x-y)
=[a^(x-y)+2b^(x-y)][a^(x-y)-2b^(x-y)]

追问

谢谢，2009^2-2008×2010
999^2+999×2+1
121×0.13+12.1×0.9-12×1.21

追答

这么多哇。。
2009^2-2008×2010
=2009^2-（2009-1)(2009+1)
=2009^2-2009^2+1
=1
999^2+999×2+1
=(999+1)^2
=1000^2
=1000000
121×0.13+12.1×0.9-12×1.21
=12.1x1.3+12.1x0.9-1.2x12.1
=12.1x(1.3+0.9-1.2)
=12.1x1
=12.1