先化简,后求值 [(x-y)3(3次方)+(x2-y2)(x-y)]/(-2x),其中x=3,y=-2

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先化简,后求值    [(x-y)3(3次方)+(x2-y2)(x-y)]/(-2x),其中x=3,y=-2

先化简,后求值 [(x-y)3(3次方)+(x2-y2)(x-y)]/(-2x),其中x=3,y=-2
先化简,后求值 [(x-y)3(3次方)+(x2-y2)(x-y)]/(-2x),其中x=3,y=-2

先化简,后求值 [(x-y)3(3次方)+(x2-y2)(x-y)]/(-2x),其中x=3,y=-2
[(x-y)3(3次方)+(x2-y2)(x-y)]/(-2x)
=(x-y)^2[(x-y)+(x+y)]/(-2x)
=(x-y)^2[2x]/(-2x)
=-(x-y)^2
=-(3+2)^2=-25

[(x-y)3(3次方)+(x2-y2)(x-y)]/(-2x)
=(x-y)^2[(x-y)+(x+y)]
=(x-y)^2*2x
=(3+2)^2*2*3
=150

如果题目没错的话就是[(x-y)(x2+xy+y2)+(x+y)(x-y)/(x-y)](-2x);[(x-y)(x2+xy+y2)+(x+y)](-2x);=6