问题
解答题
若
|
答案
∵
-1 x
=3,∴x-y=-3xy,再把它整体代入原式:1 y
=2x+3xy-2y x+2xy-y
=2(x-y)+3xy (x-y)+2xy
=-6xy+3xy -3xy+2xy
=3.-3xy -xy
故答案为3.
若
|
∵
-1 x
=3,∴x-y=-3xy,再把它整体代入原式:1 y
=2x+3xy-2y x+2xy-y
=2(x-y)+3xy (x-y)+2xy
=-6xy+3xy -3xy+2xy
=3.-3xy -xy
故答案为3.