2011年全国各地中考数学试卷试题分类汇编
第7章 分式与分式方程
一、选择题
1a
1.(2011浙江金华,7,3分)计算 – 的结果为( )
a-1a-1
1+aa
A. B. - C. -1 D.1-a a-1a-1【答案】C
2. (2011山东威海,8,3分)计算:1?A.?m?2m?1 【答案】B
3. (2011四川南充市,8,3分) 当8、分式
221?m?(m2?1)的结果是( ) 1?mC.m?2m?1
2B.?m?2m?1 D.m?1
2x?1的值为0时,x的值是( ) x?2(A)0 (B)1 (C)-1 (D)-2 【答案】B
1a
4. (2011浙江丽水,7,3分)计算 – 的结果为( )
a-1a-1
1+a
A. a-1【答案】C
5. (2011江苏苏州,7,3分)已知A.
aB. -
a-1
C. -1
D.1-a
111ab的值是 ??,则
ab2a?b11 B.- C.2 D.-2 22【答案】D
6. ( 2011重庆江津, 2,4分)下列式子是分式的是( ) A.
xxxx B. C. ?y D. 2x?123【答案】B.
m2?n27. (2011江苏南通,10,3分)设m>n>0,m+n=4mn,则的值等于
mn2
2
A. 23 【答案】A
B. 3
C. 6
D. 3
8. (2011山东临沂,5,3分)化简(x-
A.
1 x
2x-11)÷(1-)的结果是( ) xxx-1xB.x-1 C. D.
xx-1
【答案】B
a2b2?9. (2011广东湛江11,3分)化简的结果是 a?ba?bA a?b B a?b C a?b D1 22【答案】A 二、填空题
1. (2011浙江省舟山,11,4分)当x 时,分式【答案】x?3
2. (2011福建福州,14,4分)化简(1?【答案】m
2xxx
3. (2011山东泰安,22 ,3分)化简:(-)÷2的结果为 。
x+2 x-2x-4【答案】x-6
4. (2011浙江杭州,15,4)已知分式
1)(m?1)的结果是 . m?11有意义. 3?xx?3,当x=2时,分式无意义,则a= ,当a<6时,使分
x2?5x?a式无意义的x的值共有 个. 【答案】6,2
5. (2011 浙江湖州,11,4)当x=2时,分式【答案】1
6. (2011浙江省嘉兴,11,5分)当x 时,分式【答案】x?3
7. (2011福建泉州,14,4分)当x= 时,分式【答案】2;
1的值是 x?11有意义. 3?xx?2的值为零. x?2a2?b22a?2b?8. (2011山东聊城,15,3分)化简:2=__________________. 2a?2ab?ba?b【答案】
1 23x2?279. (2011四川内江,15,5分)如果分式的值为0,则x的值应为 .
x?3【答案】-3
10.(2011四川乐山11,3分)当x= 时,
1?1 x?2
【答案】3
11. (2011四川乐山15,3分)若m为正实数,且m?【答案】313
12. (2011湖南永州,5,3分)化简【答案】1.
x - 9
13. (2011江苏盐城,13,3分)化简: = ▲ .
x - 3【答案】x+3 三、解答题
1. (2011安徽,15,8分)先化简,再求值:
2
11?3,则m2?2= mma1=________. ?a?11?a12,其中x=-2. ?2x?1x?1【答案】解:原式=
x?1?2x?111?????1.
(x?1)(x?1)(x?1)(x?1)x?1?2?11x2?12. (2011江苏扬州,19(2),4分)(2)(1?)?
xx【答案】(2)解:原式=
xx?1(x?1)(x?1)x?11?== ?x(x?1)(x?1)x?1xx3. (2011四川南充市,15,6分)先化简,再求值:【答案】解:方法一:==
xx?1(-2),其中x=2. x2?1xxx?12xxx?1xx?1x== ??(?2)???2(x?1)(x?1)x(x?1)(x?1)x2?1xx2?1xx2?112xx?12xx?1?2xx?1?2x?1?x=== ???x?1(x?1)(x?1)(x?1)(x?1)(x?1)(x?1)(x?1)(x?1)(x?1)(x?1)(x?1)(x?1)?(1?x)1=?
(x?1)(x?1)x?111=?=-1 2?1x?1当x=2时,?方法二:=
x?1?xxx?1xx?12xxx?1?2x= ?(?2)=2(?)=2?(x?1)(x?1)xxxx?1xx?1xx?12x?(1?x)1=? ?(x?1)(x?1)xx?111=?=-1. 2?1x?1当x=2时,?a?3ba?b?. a?ba?ba?3b?a?b2a?2b2(a?b)???2 【答案】原式?a?ba?ba?b4. (2011浙江衢州,17(2),4分)化简: