作业帮已知A=x^2-xy-y^2,B=3xy+x^2.x,y满足条件(x-3)^2+(y+2)^2=0求1/2[2(A-B)-3A+1/3[3（A+2B）-3A]-1/2A完整
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已知A=x^2-xy-y^2,B=3xy+x^2.x,y满足条件(x-3)^2+(y+2)^2=0求1/2[2(A-B)-3A+1/3[3（A+2B）-3A]-1/2A完整
已知A=x^2-xy-y^2,B=3xy+x^2.x,y满足条件(x-3)^2+(y+2)^2=0求1/2[2(A-B)-3A+1/3[3（A+2B）-3A]-1/2A
完整
已知A=x^2-xy-y^2,B=3xy+x^2.x,y满足条件(x-3)^2+(y+2)^2=0求1/2[2(A-B)-3A+1/3[3（A+2B）-3A]-1/2A完整
(x-3)^2+(y+2)^2=0
(x-3)^2=0,(y+2)^2=0
x=3
y=-2
1/2[2(A-B)-3A+1/3[3（A+2B）-3A]-1/2A
=1/2[(A-B)-3A+A+2B-3A]-1/2A
=1/2[A-B-3A+A+2B-3A]-1/2A
=1/2[A-3A+A-3A-B+2B]-1/2A
=1/2[-4a+B]-1/2A
=-2A+1/2B-1/2A
=-5/2A+1/2B
=-5/2(x^2-xy-y^2)+1/2(3xy+x^2)
=-5/2x^2+5/2xy+5/2y^2+3/2xy+1/2x^2
=-5/2x^2+1/2x^2+5/2xy+3/2xy+5/2y^2
=-2x^2+4xy+5/2y^2
=-2*3^2+4*3*(-2)+5/2*(-2)^2
=-18-24+10
=-32
(x-3)^2+(y+2)^2=0
(x-3)^2=0,(y+2)^2=0
x=3
y=-2
因为x,y满足条件(x-3)^2+(y+2)^2=0，所以x=3,y=-2 A=11 B=-9
将A=11 B=-9代入1/2[2(A-B)-3A+1/3[3（A+2B）-3A]-1/2A
0.5[2（11+9）-3*11+1/3[3(11-18)-3*11]-1/2*11=-11
已知A=x^2-xy-y^2,B=3xy+x^2。x,y满足条件(x-3)^2+(y+2)^2=0
x-3=0 y+2=0
x=3 y=-2
差个中括号
假设为1/2[2(A-B)-3A]+1/3[3（A+2B）-3A]-1/2A
=1/2[2(A-B)-3A]+（A+2B）-A-1/2A
=(A-B)-3A/2+（A+2B）-A-1/2A
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已知A=x^2-xy-y^2,B=3xy+x^2。x,y满足条件(x-3)^2+(y+2)^2=0
x-3=0 y+2=0
x=3 y=-2
差个中括号
假设为1/2[2(A-B)-3A]+1/3[3（A+2B）-3A]-1/2A
=1/2[2(A-B)-3A]+（A+2B）-A-1/2A
=(A-B)-3A/2+（A+2B）-A-1/2A
=A-B-2A+A+2B-A
=-A+B
=-(x^2-xy-y^2)+3xy+x^2
=-x^2+xy+y^2+3xy+x^2
=4xy+y^2
=4*3*(-2)+(-2)^2
=-20
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∵x,y满足条件(x-3)^2+(y+2)^2=0
∴(x-3)^2=0且(y+2)^2=0
∴x=3，y= -2
若果你的题为1/2[2(A-B)-3A】+1/3[3（A+2B）-3A]-1/2A化简得
原式= -A+B= -x^2+xy+y^2+3xy+x^2=y^2+4xy=(-2)^+4*3*(-2)=-20
若果你的题为1/2[2(A-B)-3A+...
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∵x,y满足条件(x-3)^2+(y+2)^2=0
∴(x-3)^2=0且(y+2)^2=0
∴x=3，y= -2
若果你的题为1/2[2(A-B)-3A】+1/3[3（A+2B）-3A]-1/2A化简得
原式= -A+B= -x^2+xy+y^2+3xy+x^2=y^2+4xy=(-2)^+4*3*(-2)=-20
若果你的题为1/2[2(A-B)-3A+1/3[3（A+2B）-3A]】-1/2A化简得
原式= -A-(2/3)B= -(5/3)x^2-xy+y^2= -（5/3）3^2-3*（-2）+（-2）^2= -5
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