来自李春风的问题
去括号(5a+b)+6a5-(7-6m)(2x-7)-(4x-5)(3a方-3a-1)-(5a方+6a-8)(8mm-3m方）-5mm-2(3mn-2m方)先化简再求值3y方-x方+(x方-y)-(x方+3y方）,x=1.y=-2
去括号(5a+b)+6a5-(7-6m)(2x-7)-(4x-5)(3a方-3a-1)-(5a方+6a-8)(8mm-3m方）-5mm-2(3mn-2m方)先化简
再求值3y方-x方+(x方-y)-(x方+3y方）,x=1.y=-2
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2019-12-28 06:18