求七年级上册数学化简求值的练习题 七年级数学上册化简求值练习题50道
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1/4\uff08a+b\uff09²-6(a-b)+3/4(a+b)²+6(a-b)
5\uff08a-b\uff09²-3(a-b)²-7(a-b)-(a-b)²+7(a-b)
1/2a²-1/4b+3/2a²-3/4b-a²
-5yx²+4xy²-2xy+6x²y+2xy+5
16m+25-40m+34m
(4+2x)+(2x-x)
4a+8a-(-6a)+3a-2b
8a+4(a+2)
(2n-3)+(2n+3)-(2n-3)
7x-(5x-5y)-y
3a-4b+4a-3b
7a+3b-(4a+5b)-3
3ab-4ab+8ab-7ab+ab
(x-y)-2(x-y)
.16m+25-40m+34m
.(4+2x)+(2x-x)
4a+8a-(-6a)+3a-2b
.8a+4(a+2)
(2n-3)+(2n+3)-(2n-3)
7x-(5x-5y)-y
3a-4b+4a-3b
.7a+3b-(4a+5b)-3
3ab-4ab+8ab-7ab+ab
.(x-y)-2(x-y)
x-[y-2x-(x+y)]
3ab-4ab+8ab-7ab+ab
7x-(5x-5y)-y
23a3bc2-15ab2c+8abc-24a3bc2-8abc
-7x2+6x+13x2-4x-5x2
2y+(-2y+5)-(3y+2)
(2x2-3xy+4y2)+(x2+2xy-3y2)
2a-(3a-2b+2)+(3a-4b-1)
-6x2-7x2+15x2-2x2
2x-(x+3y)-(-x-y)-(x-y)
2x+2y-[3x-2(x-y)]
5-(1-x)-1-(x-1)
10x2-xy\uff0e
x3-2x2y+4xy2+y3\uff0e
4x2-[7x2-5x-3(1-2x+x2)]
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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=______.
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=______.
回答者： 热心网友 | 2011-2-12 10:24
2(2a2+2ab)-(3a2+4ab-b2），其中a=2，b=-1
1/4（a+b）2-6(a-b)+3/4(a+b)2+6(a-b)
5（a-b）2-3(a-b)2-7(a-b)-(a-b)2+7(a-b)
1/2a2-1/4b+3/2a2-3/4b-a2
-5yx2+4xy2-2xy+6x2y+2xy+5
16m+25-40m+34m
(4+2x)+(2x-x)
4a+8a-(-6a)+3a-2b
8a+4(a+2)
(2n-3)+(2n+3)-(2n-3)
7x-(5x-5y)-y
3a-4b+4a-3b
7a+3b-(4a+5b)-3
3ab-4ab+8ab-7ab+ab
(x-y)-2(x-y)
.16m+25-40m+34m
.(4+2x)+(2x-x)
4a+8a-(-6a)+3a-2b
.8a+4(a+2)
(2n-3)+(2n+3)-(2n-3)
7x-(5x-5y)-y
3a-4b+4a-3b
.7a+3b-(4a+5b)-3
3ab-4ab+8ab-7ab+ab
.(x-y)-2(x-y)
x-[y-2x-(x+y)]
3ab-4ab+8ab-7ab+ab
7x-(5x-5y)-y
23a3bc2-15ab2c+8abc-24a3bc2-8abc
-7x2+6x+13x2-4x-5x2
2y+(-2y+5)-(3y+2)
(2x2-3xy+4y2)+(x2+2xy-3y2)
2a-(3a-2b+2)+(3a-4b-1)
-6x2-7x2+15x2-2x2
2x-(x+3y)-(-x-y)-(x-y)
2x+2y-[3x-2(x-y)]
5-(1-x)-1-(x-1)
10x2-xy．
x3-2x2y+4xy2+y3．
4x2-[7x2-5x-3(1-2x+x2)]
打得累死了。。化简求值你自己加上就可
2(2a²+2ab)-(3a²+4ab-b²），其中a=2，b=-1
1/4（a+b）²-6(a-b)+3/4(a+b)²+6(a-b)
2(2a2+2ab)-(3a2+4ab-b2），其中a=2，b=-1
1/4（a+b）2-6(a-b)+3/4(a+b)2+6(a-b)
5（a-b）2-3(a-b)2-7(a-b)-(a-b)2+7(a-b)
1/2a2-1/4b+3/2a2-3/4b-a2
-5yx2+4xy2-2xy+6x2y+2xy+5
16m+25-40m+34m
(4+2x)+(2x-x)
4a+8a-(-6a)+3a-2b
8a+4(a+2)
(2n-3)+(2n+3)-(2n-3)
7x-(5x-5y)-y
3a-4b+4a-3b
7a+3b-(4a+5b)-3
3ab-4ab+8ab-7ab+ab
(x-y)-2(x-y)
.16m+25-40m+34m
.(4+2x)+(2x-x)
4a+8a-(-6a)+3a-2b
.8a+4(a+2)
(2n-3)+(2n+3)-(2n-3)
7x-(5x-5y)-y
3a-4b+4a-3b
.7a+3b-(4a+5b)-3
3ab-4ab+8ab-7ab+ab
.(x-y)-2(x-y)
x-[y-2x-(x+y)]
3ab-4ab+8ab-7ab+ab
7x-(5x-5y)-y
23a3bc2-15ab2c+8abc-24a3bc2-8abc
-7x2+6x+13x2-4x-5x2
2y+(-2y+5)-(3y+2)
(2x2-3xy+4y2)+(x2+2xy-3y2)
2a-(3a-2b+2)+(3a-4b-1)
-6x2-7x2+15x2-2x2
2x-(x+3y)-(-x-y)-(x-y)
2x+2y-[3x-2(x-y)]
5-(1-x)-1-(x-1)
10x2-xy．
x3-2x2y+4xy2+y3．
4x2-[7x2-5x-3(1-2x+x2)]
打得累死了。。化简求值你自己加上就可以了。
绛旓細锛1锛鍖栫畝鏁翠釜寮忓瓙銆傦紙2锛夊綋a=5/7鏃讹紝姹傚紡瀛愮殑鍊笺3銆62g+62(g+b)-b 锛1锛夊寲绠鏁翠釜寮忓瓙銆傦紙2锛夊綋g=5/7鏃讹紝姹俠鐨勮В銆4銆3(x+y)-5(4+x)+2y 锛1锛夊寲绠鏁翠釜寮忓瓙銆5銆(x+y)(x-y)锛1锛夊寲绠鏁翠釜寮忓瓙銆6銆2ab+a脳a-b 锛1锛夊寲绠鏁翠釜寮忓瓙銆7銆5.6x+4(x+y)-y 锛1锛夊寲绠...
绛旓細1銆=4a骞虫柟+4ab-3a骞虫柟-4ab+b骞虫柟 =a骞虫柟+b骞虫柟 2銆=1/4(a+b)骞虫柟+3/4(a+b)骞虫柟-6(a-b)+6(a-b)=(a+b)骞虫柟-b)=a骞虫柟+2ab+b骞虫柟 3銆=5(a-b)骞虫柟-3(a-b)骞虫柟-(a-b)骞虫柟-7(a-b)+7(a-b)=(a-b)骞虫柟 =a骞虫柟-2ab+b骞虫柟 4銆=1/2a骞虫柟+3/2a骞虫柟-1/4b-3/...
绛旓細鏁板鍖栫畝棰 1銆-9(x-2)-y(x-5) 锛1锛夊寲绠鏁翠釜寮忓瓙銆傦紙2锛夊綋x=5鏃讹紝姹倅鐨勮В銆2銆5(9+a)脳b-5(5+b)脳a 锛1锛夊寲绠鏁翠釜寮忓瓙銆傦紙2锛夊綋a=5/7鏃讹紝姹傚紡瀛愮殑鍊笺3銆62g+62(g+b)-b 锛1锛夊寲绠鏁翠釜寮忓瓙銆傦紙2锛夊綋g=5/7鏃讹紝姹俠鐨勮В銆4銆3(x+y)-5(4...
绛旓細33锛嶽5a2+( )a-7]+[( )a2-4a+( )]=a2+2a+1锛34锛3x-[y-(2x+y)]=___锛35锛鍖栫畝|1-x+y|-|x-y|(鍏朵腑x锛0,y锛0)绛変簬___锛36锛庡凡鐭鈮,x+y-|x-y|=___锛37锛庡凡鐭锛0,y锛0,鍖栫畝|x+y|-|5-x-y|=___锛38锛4a2n-an-(3an-2a2n)锛漘__锛39锛庤嫢涓涓椤瑰紡...
绛旓細鈭村綋x=-22鏃跺師寮忕殑鍊=75853 2.鈻弇鈻=3,鈻弉鈻=2.涓攎-n锛0 鈭磎=-3,n=2鎴-2 鈭9m²-[7(m²-2/7路n)-3(1/3路m²-n)-1]-1/2 =9m²-(7m²-2n-m²+3n-1)-1/2 =3m²-n+1/2 鈭村綋m=-3,n=2鏃跺師寮忕殑鍊=3脳锛-3锛²...
绛旓細35锛鍖栫畝|1-x+y|-|x-y|(鍏朵腑x锛0锛寉锛0)绛変簬___锛36锛庡凡鐭鈮锛寈+y-|x-y|=___锛37锛庡凡鐭锛0锛寉锛0锛屽寲绠|x+y|-|5-x-y|=___锛38锛4a2n-an-(3an-2a2n)锛漘__锛39锛庤嫢涓涓椤瑰紡鍔涓-3x2y+2x2-3xy-4寰 2x2y+3xy2-x2+2xy锛屽垯杩欎釜澶氶」寮忎负___锛40锛-5xm-x...
绛旓細姹傚垵涓鏁板棰樻眰澶氶亾涓鍏冧竴娆℃柟绋,鍖栫畝姹傚棰,瓒婂瓒 涓.瑙ｇ瓟棰(鍏30灏忛) 1.(2005•瀹佸痉)瑙ｆ柟绋:2x+1=7 2. 3.(1)瑙ｆ柟绋:4锕=3(2锕); (2)瑙ｆ柟绋:. 4.瑙ｆ柟绋:. 5.瑙ｆ柟绋 (1)4(x锕1)锕3(20锕)=5(x锕2); (2)x锕=2锕. 6.(1)瑙ｆ柟绋:3(x锕1)=2x+3; (2)瑙ｆ柟绋:=x锕...
绛旓細鏂规硶涓锛歑Y=5甯﹀叆 =锛6*5+7y锛+銆8x-锛5*5-y+6x锛夈=30+7y+锛8x-25+y-6x锛=5+8y+2x =5+2锛坸+4y锛夛紙x+4y锛=-1甯﹀叆 =5-2 =3 鏂规硶浜岋細=锛6*5+7y锛+銆8x-锛5*5-y+6x锛夈=30+7y+锛8x-25+y-6x锛=5+8y+2x 鍥犱负x+4y=-1 鎵浠=-1-4y 甯﹀叆 =5+8y+2锛-1-...
绛旓細锛漘__锛6锛鍖栫畝浠ｆ暟寮4x2-[7x2-5x-3(1-2x+x2)]鐨勭粨鏋滄槸___锛7锛2a-b2+c-d3=2a+( )-d3=2a-d3-( )=c-( )锛8锛3a-(2a-3b)+3(a-2b)-b=___锛9锛庡寲绠浠ｆ暟寮弜-[y-2x-(x+y)]绛変簬___锛10锛嶽5a2+( )a-7]+[( )a2-4a+( )]=a2+2a+1锛
绛旓細瑙ｅ師寮 =2(x+y)^2-3(x-y)^2+[4(x+y)^5脳(x-y)^4]梅[(x+y)^4(x-y)^4]=2脳3^2-3脳1^2+4(x+y)=18-3+4脳3 =27
