中考专项训练——计算题
集训一
(计算)
1. (2011.常州)计算:Sin45?
012?38
2.(2011.淮安)计算:
1
3.(2011.连云港)计算:2×(-5)+23-3÷ .
2
4.(2011.南通)计算:22+(-1)4+(5-2)0-|-3|;
5.(2011。苏州)计算:2+|﹣1|﹣
6.(2011.宿迁)计算:?2?(?2)?2sin30?.
02
.
7.(2011.泰州)计算
8.(2011.无锡)计算:
(1)??1??16???2? (2)a(a-3)+(2-a)(2+a)
20,
01-2
9.(2011.盐城)计算:(3)-()+tan45°
2
10.计算:?
303???2011??4???2? 2答案
1.解;原式=
22??2?2 222.解:原式=5+4-1=8
3.解:原式=-10+8-6=-8
4.解:原式=4+1+1-3=3。 5.解:原式=4+1﹣3=2. 6.解:原式=2+1+2×
1=3+1=4. 27.解:原式=1+2﹣
2+2×=1+2﹣
0+=3.
8.1) 解:??1??16???2?=1-4+1=-2
2)解:a?a?3???2?a??2?a??a2?3a?4?a2=4?3a
9.解:原式=1-4+1=-2.
10.解:原式=
31?1?=0. 22
集训二
(分式化简)
1. (2011.南京)计算
2.(2011.常州)化简:
.
2x1 ?x2?4x?2
2
3.(2011.淮安)化简:(a+b)+b(a﹣b).
4.(2011.南通)先化简,再求值:(4ab3-8a2b2)÷4ab+(2a+b)(2a-b),其中a=2,b=1.
5.(2011.苏州)先化简,再求值:(a﹣1+)÷(a+1),其中a=
2
﹣1.
6.(2011.宿迁)已知实数a、b满足ab=1,a+b=2,求代数式a2b+ab2的值.
7.(2011.泰州)化简.
8.(2011.无锡)a(a-3)+(2-a)(2+a)
9.(2011.徐州)化简:(a?)?
2?1?x?110.(2011.扬州)化简?1???
x?x?1aa?1; a
答案
1.解:原式=﹣?,
=﹣,
=+,
=,
=
,
2.解:原式=
1 x?23.解;原式=a2+3ab
4.解:原式=4ab(b2-2ab)÷4ab+4a2-b2=b2-2ab+4a2-b2=4a2-2ab 当a=2,b=1时,原式=4×22-2×2×1=16-4=12。
5.解:原式=()?,
=?,
=当a=
, ﹣1时,
原式==.
6.解:当ab=1,a+b=2时,原式=ab(a+b)=1×2=2. 7.解:
原式=?=.
8.解:a?a?3???2?a??2?a??a2?3a?4?a2=4?3a 9.解;原式=a+1 10. 解:原式=
=
x?1x ·2xx?1x?1x· x?x?1??x?1?=
1. x?1