4x²y-[6xy-3(4xy-2)-x²y]+1
=4x²y-(6xy-12xy+6-x²y)+1
=5x²y+6xy-5
=xy(5x+6)-5
因为x=2,y=2分之1,所以:
4x²y-[6xy-3(4xy-2)-x²y]+1
=2*11/2*(5*2+6)-5
=11*16-5
=171
4x²y-[6xy-3(4xy-2)-x²y]+1
=4x²y-(6xy-12xy+6-x²y)+1
=5x²y+6xy-5
=xy(5x+6)-5
因为x=2,y=2分之1,所以:
4x²y-[6xy-3(4xy-2)-x²y]+1
=2*11/2*(5*2+6)-5
=11*16-5
=171