(8xy-3x平方)-5xy-2(3xy-2x平方),其中,x=2,y=-1

问题描述:

(8xy-3x平方)-5xy-2(3xy-2x平方),其中,x=2,y=-1

(8xy-3x平方)-5xy-2(3xy-2x平方)
=8xy-3x²-5xy-6xy+4x²
=x²-3xy
=4+6
=10