问题
解答题
4x2y-[6xy-2(4xy-2)-x2y]+1,其中x=-
|
答案
原式=4x2y-(6xy-8xy+4-x2y)+1
=4x2y-6xy+8xy-4+x2y+1,
=5x2y+2xy-3,
当x=-
,y=-1时.原式=-31 2
.1 4
4x2y-[6xy-2(4xy-2)-x2y]+1,其中x=-
|
原式=4x2y-(6xy-8xy+4-x2y)+1
=4x2y-6xy+8xy-4+x2y+1,
=5x2y+2xy-3,
当x=-
,y=-1时.原式=-31 2
.1 4