化简、求值(1)化简:3(x-2y)+2(3x+y)(2)先化简再求值(3x²y-2xy²)-(xy
4个回答
3(x-2y)+2(3x+y)
=9x-4y
(3x²y-2xy²)-(xy²-2x²y)
=xy(3x-2y)-xy(y-2x)
=xy(5x-3y)
=22
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