(3x-2y)(4x-5y)-11(x+y)(x-y)+5xy,已知X=3又1/2,y=2又1/3

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(3x-2y)(4x-5y)-11(x+y)(x-y)+5xy,已知X=3又1/2,y=2又1/3(3x-2y)(4x-5y)-11(x+y)(x-y)+5xy,已知X=3又1/2,y=2又1/3(3

(3x-2y)(4x-5y)-11(x+y)(x-y)+5xy,已知X=3又1/2,y=2又1/3
(3x-2y)(4x-5y)-11(x+y)(x-y)+5xy,已知X=3又1/2,y=2又1/3

(3x-2y)(4x-5y)-11(x+y)(x-y)+5xy,已知X=3又1/2,y=2又1/3
(3x-2y)(4x-5y)-11(x+y)(x-y)+5xy
=12x^2-23xy+10y^2-11x^2+11y^2+5xy
=x^2-18xy+21y^2
=x^2-10xy+21y^2-8xy
=(x-3y)(x-7y)-8xy
=(7/2-3*7/3)(7/2-7*7/3)-8*7/2*7/3
=7/2*77/6-392/6
=-245/12