先化简再求值先化简再求值:4分之1x²y+3分之1x²y+3[-(9分之1x²y+xy)]+4分之3x²y,其中x=-1,Y=1.求解……很着急!

先化简再求值先化简再求值:4分之1x²y+3分之1x²y+3[-(9分之1x²y+xy)]+4分之3x²y,其中x=-1,Y=1.求解……很着急!
先化简再求值
先化简再求值:4分之1x²y+3分之1x²y+3[-(9分之1x²y+xy)]+4分之3x²y,其中x=-1,Y=1.求解……很着急!

先化简再求值先化简再求值:4分之1x²y+3分之1x²y+3[-(9分之1x²y+xy)]+4分之3x²y,其中x=-1,Y=1.求解……很着急!
等于-2吧

=(1/4+1/3-1/3+2/4)x²y+3xy
=x²y+3xy
=(x+3)xy
x=-1,y=1代入
原式=(-1+3)*-1*1=-2

4分之1x²y+3分之1x²y+3[-(9分之1x²y+xy)]+4分之3x²y
=1/4x²y+1/3x²y-1/3x²y+3xy+3/4x²y
=x²y+3xy
其中x=-1,Y=1
上式=(-1)²*1+3*(-1)*1
=1-3
=-2

4分之1x²y+3分之1x²y+3[-(9分之1x²y+xy)]+4分之3x²y
=xy[x+3]
当x=-1,Y=1时，
xy[x+3]
=-2

原式=X2y+3xy，将x=-1,y=1代入得-2