(-2)0-+Р=2+(-3)×1-3+(-1)Р=2-3-3-1Р=-5﹒Р(2)(4ab3+8a2b2)÷4ab+ (a-b)(3a+b)Р解答:(4ab3+8a2b2)÷4ab+ (a-b)(3a+b)Р=b2+2ab+3a2+ab-3ab-b2Р=3a2﹒Р18.(10分)先化简,再求值:Р(1)[2x(x2y-xy2)+xy(xy-x2)]÷x2y,其中x=2017,y=2016.Р解答:[2x(x2y-xy2)+xy(xy-x2)]÷x2yР=[2x3y-2x2y2+x2y2-x3y] ÷x2yР=[x3y-x2y2] ÷x2yР=x-yР当x=2017,y=2016时,原式=2017-2016=1﹒Р(2)(2m-n)2+(2m-n)(-2m-n),其中m,n满足方程组﹒Р解答:解方程组,得,Р(2m-n)2+(2m-n)(-2m-n)Р=4m2-2mn+n2-(2m-n)(2m+n)Р=4m2-2mn+n2-4m2+n2Р=-2mn+n2Р当m=3,n=-1时,原式=-2×3×(-1)+ ×(-1)2=-5﹒Р19.(8分)小明与小亮在做游戏,两人各报一个整式,小明报的整式作被除式,小亮报的整式作除式,要求商式必须为2xy﹒若小明报的是x3y-2xy2,小亮应报什么整式?若小亮也报x3y-2xy2,那么小明能报一个整式吗?说说你的理由﹒Р解答:当小明报x3y-2xy2时,(x3y-2xy2)÷2xy=x3y÷2xy-2xy2÷2xy=x2-y,Р所以小亮报的整式是x2-y;Р小明也能报一个整式,理由如下:Р∵(x3y-2xy2)·2xy=x3y·2xy-2xy2·2xy=2x4y2-4x2y3,Р∴小明报的整式是2x4y2-4x2y3.Р20.(8分)观察下列关于自然数的等式:Р22﹣9×12=-5 ①Р52﹣9×22=-11 ②Р82﹣9×32=-17 ③
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