已知1△3=1×2×3,3△5=3×4×5×6×7,那么8△3=?

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已知1△3=1×2×3,3△5=3×4×5×6×7,那么8△3=?
已知1△3=1×2×3,3△5=3×4×5×6×7,那么8△3=?

已知1△3=1×2×3,3△5=3×4×5×6×7,那么8△3=?
8△3=8×9×10=720

2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)

(2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)
=2x+3y-2xy-x-4y-xy-(3xy+2y-2x-3)
=x-y-3xy-(3xy+2y-2x-3)
=(x-y)-3xy-【3xy-2(x-y)-3】
=(x-y)-3xy-3xy+2(x-y)+...

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2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)

(2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)
=2x+3y-2xy-x-4y-xy-(3xy+2y-2x-3)
=x-y-3xy-(3xy+2y-2x-3)
=(x-y)-3xy-【3xy-2(x-y)-3】
=(x-y)-3xy-3xy+2(x-y)+3
=(x-y)-6xy+2(x-y)+3
=3(x-y)-6xy+3
=9+12+3
=24
2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)

(2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)
=2x+3y-2xy-x-4y-xy-(3xy+2y-2x-3)
=x-y-3xy-(3xy+2y-2x-3)
=(x-y)-3xy-【3xy-2(x-y)-3】
=(x-y)-3xy-3xy+2(x-y)+3
=(x-y)-6xy+2(x-y)+3
=3(x-y)-6xy+3
=9+12+3
=24
2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)

(2x+3y-2xy)-(x+4y+xy)-(3xy+2y-2x-3)
=2x+3y-2xy-x-4y-xy-(3xy+2y-2x-3)
=x-y-3xy-(3xy+2y-2x-3)
=(x-y)-3xy-【3xy-2(x-y)-3】
=(x-y)-3xy-3xy+2(x-y)+3
=(x-y)-6xy+2(x-y)+3
=3(x-y)-6xy+3
=9+12+3
=24

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