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10道初一数学化简求值题

发布时间：2025-10-07 | 来源：互联网转载和整理

3．3ab-4ab+8ab-7ab+ab=______．

4．7x-(5x-5y)-y=______．

5．23a3bc2-15ab2c+8abc-24a3bc2-8abc=______．

6．-7x2+6x+13x2-4x-5x2=______．

7．2y+(-2y+5)-(3y+2)＝______．

11．(2x2-3xy+4y2)+(x2+2xy-3y2)=______．

12．2a-(3a-2b+2)+(3a-4b-1)=______．

13．-6x2-7x2+15x2-2x2＝______．

14．2x-(x+3y)-(-x-y)-(x-y)＝______．

16．2x+2y-[3x-2(x-y)]=______．

17．5-(1-x)-1-(x-1)=______．

18．()+(4xy+7x2-y2)=10x2-xy．

19．(4xy2-2x2y)-()=x3-2x2y+4xy2+y3．

21．已知A=x3-2x2+x-4,B=2x3-5x+3,计算A+B=______．

22．已知A=x3-2x2+x-4,B=2x3-5x+3,计算A-B=______．

23．若a=-0.2,b=0.5,代数式-(|a2b|-|ab2|)的值为______．

25．一个多项式减去3m4-m3-2m+5得-2m4-3m3-2m2-1,那么这个多项式等于______．

26．-(2x2-y2)-[2y2-(x2+2xy)]=______．

27．若-3a3b2与5ax-1by+2是同类项,则x=______,y=______．

28．(-y+6+3y4-y3)-(2y2-3y3+y4-7)＝______．

29．化简代数式4x2-[7x2-5x-3(1-2x+x2)]的结果是______．

30．2a-b2+c-d3=2a+()-d3=2a-d3-()=c-()．

31．3a-(2a-3b)+3(a-2b)-b=______．

32．化简代数式x-[y-2x-(x+y)]等于______．

33．[5a2+()a-7]+[()a2-4a+()]=a2+2a+1．

34．3x-[y-(2x+y)]=______．

35．化简|1-x+y|-|x-y|(其中x＜0,y＞0)等于______．

36．已知x≤y,x+y-|x-y|=______．

37．已知x＜0,y＜0,化简|x+y|-|5-x-y|=______．

38．4a2n-an-(3an-2a2n)＝______．

39．若一个多项式加上-3x2y+2x2-3xy-4得

2x2y+3xy2-x2+2xy,

则这个多项式为______．

40．-5xm-xm-(-7xm)+(-3xm)=______．

41．当a=-1,b=-2时,

[a-(b-c)]-[-b-(-c-a)]＝______．

43．当a=-1,b=1,c=-1时,

-[b-2(-5a)]-(-3b+5c)＝______．

44．-2(3x+z)-(-6x)+(-5y+3z)=______．

45．-5an-an+1-(-7an+1)+(-3an)＝______．

46．3a-(2a-4b-6c)+3(-2c+2b)=______．

48．9a2+[7a2-2a-(-a2+3a)]=______．

50．当2y-x=5时,5(x-2y)2-3(-x+2y)-100=_____