整式计算

11.2x-(3x-2y+3)-(5y-2)2.-(3a+2b)+(4a-3b+1)-(2a-b-3)3.ab-4ab+8ab-7ab+ab4．7x-(5x-5y)-y5．23a3bc2-15ab2c+8abc-24a3bc2-8abc6．-7x2+6x+13x2-4x-5x27．2y+(-2y+5)-(3y+2)8．(2x2-3xy+4y2)+(x2+2xy-3y2)9．2a-(3a-2b+2)+(3a-4b-1)9．-6x2-7x2+15x2-2x210．11．2x-(x+3y)-(-x-y)-(x-y)12．2x+2y-[3x-2(x-y)]13．5-(1-x)-1-(x-1)14．()+(4xy+7x2-y2)=10x2-xy．15．(4xy2-2x2y)-()=x3-2x2y+4xy2+y3．16．已知A=x3-2x2+x-4,B=2x3-5x+3,计算A+B17．已知A=x3-2x2+x-4,B=2x3-5x+3,计算A-B18．若a=-0.2,b=0.5,代数式-(|a2b|-|ab2|)的值19．一个多项式减去3m4-m3-2m+5得-2m4-3m3-2m2-1,那么这个多项式等于220．-(2x2-y2)-[2y2-(x2+2xy)]21．若-3a3b2与5ax-1by+2是同类项,则x=______,y=______．22．(-y+6+3y4-y3)-(2y2-3y3+y4-7)＝______．23．化简代数式4x2-[7x2-5x-3(1-2x+x2)]的结果是______．24．2a-b2+c-d3=2a+()-d3=2a-d3-()=c-()．25．3a-(2a-3b)+3(a-2b)-b26．x-[y-2x-(x+y)]27．[5a2+()a-7]+[()a2-4a+()]=a2+2a+1．28．3x-[y-(2x+y)]29．化简|1-x+y|-|x-y|(其中x＜0,y＞0)等于______．30．已知x≤y,x+y-|x-y|=______．31．已知x＜0,y＜0,化简|x+y|-|5-x-y|=______．32．4a2n-an-(3an-2a2n)33．若一个多项式加上-3x2y+2x2-3xy-4得2x2y+3xy2-x2+2xy,则这个多项式为______．34．-5xm-xm-(-7xm)+(-3xm)35．当a=-1,b=-2时,[a-(b-c)]-[-b-(-c-a)]＝______．36．当a=-1,b=1,c=-1时,-[b-2(-5a)]-(-3b+5c)＝______．37．-2(3x+z)-(-6x)+(-5y+3z)338．-5an-an+1-(-7an+1)+(-3an)39．3a-(2a-4b-6c)+3(-2c+2b)40．9a2+[7a2-2a-(-a2+3a)]4当2y-x=5时,5(x-2y)2-3(-x+2y)-100(二)选择42．下列各式中计算结果为-7x-5x2+6x3的是[]A．3x-(5x2+6x3-10x)；B．3x-(5x2+6x3+10x)；C．3x-(5x2-6x3+10x)；D．3x-(5x2-6x3-10x)．43．把(-x-y)+3(x+y)-5(x+y)合并同类项得[]A．(x-y)-2(x+y)；B．-3(x+y)；C．(-x-y)-2(x+y)；D．3(x+y)．44．2a-[3b-5a-(2a-7b)]等于[]A．-7a+10b；B．5a+4b；C．-a-4b；D．9a-10b．45．减去-3m等于5m2-3m-5的代数式是[]A．5(m2-1)；B．5m2-6m-5；C．5(m2+1)；D．-(5m2+6m-5)．46．将多项式2ab-9a2-5ab-4a2中的同类项分别结合在一起,应为[]A．(9a2-4a2)+(-2ab-5ab)B．(9a2+4a2)-(2ab-5ab)C．(9a2-4a2)-(2ab+5ab)D．(9a2-4a2)+(2ab-5ab)．47．当a=2,b=1时,-a2b+3ba2-(-2a2b)等于[]A．20；B．24；C．0；D．16．48．若A和B均为五次多项式,则A-B一定是[]A．十次多项式；B．零次多项式；C．次数不高于五次的多项式；D．次数低于五次的多项式．49．-｛[-(x+y)]｝+｛-[(x+y)]｝等于[]A．0；B．-2y；C．x+y；D．-2x-2y．50．若A=3x2-5x+2,B=3x2-5x+6,则A与B的大小是[]A．A＞B；B．A=B；C．A＜B；D．无法确定．51．当m=-1时,-2m2-[-4m2+(-m2)]等于[]A．-7；B．3；C．1；D．2．52．当m=2,n=1时,多项式4-m-[-(2m-3n)]+[-(-3m)-4n]等于[]A．1；B．9；C．3；D．5．53．-5an-an-(-7an)+(-3an)等于[]A．-16an；B．-16；C．-2an；D．-2．54．(5a-3b)-3(a2-2b)等于[]A．3a2+5a+3b；B．2a2+3b；C．2a3-b2；D．-3a2+5a-5b．55．x3-5x2-4x+9等于[]A．(x3-5x2)-(-4x+9)；B．x3-5x2-(4x+9)；C．-(-x3+5x2)-(4x-9)；D．x3+9-(5x2-4x)．56．4x2y-5xy2的结果应为[]A．-x2y；B．-1；C．-x2y2；D．以上答案都不对．(三)化简57．(4x2-8x+5)-(x3+3x2-6x+2)．58．(0.3x3-x2y+xy2-y3)-(-0.5x3-x2y+0.3xy2)．59．-{2a2b-[3abc-(4ab2-a2b)]｝．60．(5a2b+3a2b2-ab2)-(-2ab2+3a2b2+a2b)．61．(x2-2y2-z2)-(-y2+3x2-z2)+(5x2-y2+2z2)．62．(3a6-a4+2a5-4a3-1)-(2-a+a3-a5-a4)．63．(4a-2b-c)-5a-[8b-2c-(a+b)]．64．(2m-3n)-(3m-2n)+(5n+m)．65．(3a2-4ab-5b2)-(2b2-5a2+2ab)-(-6ab)．66．xy-(2xy-3z)+(3xy-4z)．67．(-3x3+2x2-5x+1)-(5-6x-x2+x3)．68．3x-(2x-4y-6x)+3(-2z+2y)．69．(-x2+4+3x4-x3)-(x2+2x-x4-5)．70．若A=5a2-2ab+3b2,B=-2b2+3ab-a2,计算A+B．571．已知A=3a2-5a-12,B=2a2+3a-4,求2(A-B)．72．2m-{-3n+[-4m-(3m-n)]｝．73．5m2n+(-2m2n)+2mn2-(+m2n)．74．4(x-y+z)-2(x+y-z)-3(-x-y-z)．75．2(x2-2xy+y2-3)+(-x2+y2)-(x2+2xy+y2)．76．2(a2-ab-b2)-3(4a-2b)+2(7a2-4ab+b2)．77．2x2-｛-3x-[4x2-(3x2-x)+(x-x2)]｝．78．-(7x-y-2z)-｛[4x-(x-y-z)-3x+z]-x｝．79．(+3a)+(-5a)+(-7a)+(-31a)-(+4a)-(-8a)．80．a3-(a2-a)+(a2-a+1)-(1-a4+a3)．81．4x-2(x-3)-3[x-3(4-2x)+8]．(四)将下列各式先化简,再求值82．已知a+b=2,a-b=-1,求3(a+b)2(a-b)2-5(a+b)2×(a-b)2的值．已A=a2+2b2-3c2,B=-b2-2c2+3a2,C=c2+2a2-3b2,求(A-B)+C．84．求(3x2y-2xy2)-(xy2-2x2y),其中x=-1,y=2．85．已知|x+1|+(y-2)2=0,求代数式5(2x-y)-3(x-4y)的值．86．当P=a2+2ab+b2,Q=a2-2ab-b2时,求P-[Q-2P-(P-Q)]．87．求2x2-｛-3x+5+[4x2-(3x2-x-1)]｝的值,其6中x=-3．88．当x=-2,y=-1,z=3时,求5xyz-｛2x2y-[3xyz-(4xy2-x2y)]｝的值．89．已知A=x3-5x2,B=x2-6x+3,求A-3(-2B)．