已知x-y=6,xy=-1,求(2x+3x-2xy)-(x+4y+xy)-(3yx-2x+2y)的值_数学解答

已知x-y=6,xy=-1,求(2x+3x-2xy)-(x+4y+xy)-(3yx-2x+2y)的值

人气：443 ℃　时间：2019-08-19 22:29:57

解答

(2x+3x-2xy)-(x+4y+xy)-(3yx-2x+2y)
=5x-2xy-x-4y-xy-3xy+2x-2y
=6x-6xy-6y
=6(x-y)-6xy
=36+6
=42