(1)3xy∧2-3[xy-2(xy-1/2xy∧2)+2xy],其中x=-2,y=1(2)已知A=-x∧2+3x-1,B=-2x∧ 2+x+1,计算当x=-2时,2A-B的值.先化简再求值

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(1)3xy∧2-3[xy-2(xy-1/2xy∧2)+2xy],其中x=-2,y=1(2)已知A=-x∧2+3x-1,B=-2x∧2+x+1,计算当x=-2时,2A-B的值.先化简再求值(1)3xy

(1)3xy∧2-3[xy-2(xy-1/2xy∧2)+2xy],其中x=-2,y=1(2)已知A=-x∧2+3x-1,B=-2x∧ 2+x+1,计算当x=-2时,2A-B的值.先化简再求值
(1)3xy∧2-3[xy-2(xy-1/2xy∧2)+2xy],其中x=-2,y=1
(2)已知A=-x∧2+3x-1,B=-2x∧ 2+x+1,计算当x=-2时,2A-B的值.先化简再求值

(1)3xy∧2-3[xy-2(xy-1/2xy∧2)+2xy],其中x=-2,y=1(2)已知A=-x∧2+3x-1,B=-2x∧ 2+x+1,计算当x=-2时,2A-B的值.先化简再求值
解3xy∧2-3[xy-2(xy-1/2xy∧2)+2xy],
=3xy∧2-3[xy-2xy+1xy∧2+2xy],
=3xy∧2-3xy+6xy-3xy∧2-6xy,
=-3xy
=-3*(-2)*1
=6
A=-x∧2+3x-1,B=-2x∧ 2+x+1
2A-B
=2(-x∧2+3x-1)-(-2x∧ 2+x+1)
=-2x∧2+6x-2+2x∧ 2-x-1
=5x-3
=5*(-2)-3
=-13

1)3xy∧2-3[xy-2(xy-1/2xy∧2)+2xy], =3xy∧2-3xy+6xy-3xy∧2-6xy=-3xy当x=-2,y=1时,原式=-3×(-2)×1=6(2)已知A=-x∧2+3x-1,B=-2x∧ 2+x+1,计算当x=-2时,的值。2A-B=2(-x∧2+3x-1)-(-2x∧ 2+x+1)=-2x∧2-6x+2+2x∧ 2-x-1=-7x+1当x=-2时,原式=-7×(-2)+1=15