2005年襄樊市初中升学统一考试
数学试题
卷Ⅰ 选择题(36分)
一、选择题(本大题共12道小题,每小题3分,共36分,在每小题给出的四个选项中,只
有一项是符合题目要求的,请将其序号在答题卡中涂黑作答.)
1.某地一天早晨的气温是℃,中午上升了11℃,午夜又下降了9℃,则午夜的气温是
A.5℃ B.℃ C.℃ D.℃
2.下列计算错误的是
A. B.
C. D.
3.实数在数轴上表示如图1所示,则下列结论错误的是
图1
A. B. C. D.
4.某商场对一种家电商品作调价,按原价的8折出售,仍可获利10%,此商品的原价是2200元,则商品的进价是
A.1540元 B.1600元 C.1690元 D.1760元
5.下列说法正确的是
A.若,则 B.,则
C. D.5的平方根是
6.若方程组有一个实数解,则的值是
A. B. C. D.
7.在匀速运动中,路程(千米)一定时,速度(千米/时)关于时间(小时)的函数图象大致是
A B C D
图2
8.下列四个生活、生产现象:①用两个钉子就可以把木条固定在墙上;②植树时,只要定出两棵树的位置,就能确定同一行树所在的直线;③从地到地架设电线,总是尽可能沿着线段架设;④把弯曲的公路改直,就能缩短路程,其中可用公理“两点之间,线段最短”来解释的现象有
A.①② B.①③ C.②④ D.③④
9.如图3,是对角线上两点,且,连结、,则图中共有全等三角形的对数是
|
A.1对 B.2对 C.3对 D.4对
10.的半径为5cm,弦,,则和的距离是
A.7cm B.8cm C.7cm或1cm D.1cm
11.一块半径为30cm,圆心角为的扇形铁皮,做成一个圆锥的侧面(粘合部分忽略不计),则该圆锥的底面半径是
A.30cm B.20cm C.10cm D.15cm
12.甲、乙两人各打靶5次,已知甲所中的环数是8,7,9,7,9,乙所中的环数的平均数是,方差,那么对甲、乙射击成绩正确判断是
A.乙的射击成绩较稳定 B.甲的射击成绩较稳定
C.甲、乙的射击成绩稳定性相同 D.甲、乙的射击成绩无法比较
卷Ⅱ 非选择题(84分)
二、填空题(本大题共6道小题,每小题3分,共18分,把答案填在题中横线上)
13.分解因式: .
14.若一次函数的图象不过第一象限,则的取值范围是 .
15.同一时刻,高为1.5m标杆影长为2.5m,一古塔在地面的影长为50m,那么古塔的高为
m.
16.已知实数满足等式,,则的值是 .
17.如图4,已知半圆的直径4cm,点是这个
半圆的三等分点,则弦和围成的阴影部分面
积为 cm2.
18.如图5,用有花纹和没有花纹的两种正方形地面砖按图5中所示的规律拼成若干图案,则第个图案中没有花纹的地面砖有 块.
第一个图案 第二个图案 第三个图案
三、解答题(本大题共8道小题,共计66分,解答应写出文字说明、证明过程或演算步骤)
19.(本题满分6分)
先化简,在求值
.其中
20.(本题满分6分)
今年,某县(市)有14000名考生参加了理化生实验操作考试,现随机抽查100名考生的考试成绩(满分100分,分数取整数),列出频率分布表如下:
(1) 补全频率分布表;
(2) 若规定考试成绩不低于80分的为优秀,则这次考试的优秀率是多少?该县(市)理
化实验操作考试成绩为优秀的约有多少名?
分组 | 频数 | 频率 |
39.5~49.5 | 6 | 0.06 |
49.5~59.5 | 10 | 0.10 |
59.5~69.5 | 22 | |
69.5~79.5 | 0.20 | |
79.5~89.5 | ||
89.5~100.5 | 16 | 0.16 |
合计 | 100 | 1.00 |
21.(本题满分6分)
解方程
22.(本题满分7分)
我们在探索平面图形性质时,往往通过剪拼的方式帮助我们寻找解题思路,例如,在证明三角形中位线性质定理时,就采用了图6-1的剪拼方式,将三角形转化为平行四边形使问题得以解决,请你仿照6-1的方法,在图6-2和图6-3中,分别只剪拼一次,实现下列转化:
(1) 将平行四边形转化为矩形;(2)将梯形转化为三角形
要求:选择其中一个图形,用尺规作出剪切线,保留痕迹,不写作法、其他画图,工具不限.
23.(本题满分7分)
如图7,一块四边形土地,其中m,
m,求这块土地的面积
24.种植草莓大户张华现有22吨草莓等售,有两种销售渠道,一是运往省城直接批发给零售商,二是在本地市场零售,经过调查分析,这两种销售渠道每天销量及每吨所获纯利润见下表:
销售渠道 | 每日销量 (吨) | 每吨所获纯 利润(元) |
省城批发 | 4 | 1200 |
本地零售 | 1 | 2000 |
受客观因素影响,张华每天只能采用一种销售渠道,草莓必须在10日内售出.
(1)若一部分草莓运往省城批发给零售商,其余在本地市场零售,请写出销售22吨草莓所获纯利润(元)与运往省城直接批发零售商的草莓量(吨)之间的函数关系式;
(2) 怎样安排这22吨草莓的销售渠道,才使张华所获纯利润最大?并求出最大纯利润.
25.(本题满分11分)
如图8,已知:是的直径,分别是的切线,切点分别为是和的延长线的交点.
(1) 猜想与的位置关系,并加以证明;
(2) 设的积为,的半径为,试探究与的关系;
(3)当时,求和的值.
26.(本题满分13分)
已知:是的半径,以为直径的与的弦相交于点,在如图9所示的直角坐标系中,交轴于点,连结.
(1) 当点在第一象限上移动时,写出你认为正确的结论:
(至少写出四种不同类型的结论);
(2) 若线段的长是关于的方程的两根,且
,求以点为顶点且经过点的抛物线的解析式;
(3)该抛物线上是否存在点,使得是以为直角边的直角三角形?若存在,求出点的坐标;若不存在,说明其理由.
2005年襄樊市初中升学统一考试
数学试题参考答案及评分标准
一、选择题(共12个小题,每小题3分,共计36分)
题 号 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
答 案 | B | C | D | B | C | A | A | D | C | C | C | A |
二、填空题(共6个小题,每小题3分,共计18分)
13. 14. 15.30
16.2或(填对1个只给1分) 17. 18.
二、解答题(共计66分)
19.解:原式················································ 1分
·············································································· 2分
································································ 4分
当时,
原式············································································ 5分
······························································································· 6分
20.解:(1)从上到下从左到右依次填写:0.22,20,26,0.26···························· 3分
(前两空每空1分,后两空每空0.5分)
(2)优秀率为:·················································· 4分
······················································································ 5分
答:优秀率为42%,该县(市)考试成绩为优秀的大约有人··················· 6分
21.解:设,则原方程可变形为.········································ 1分
方程两边同乘以,约去分母,得.·································· 2分
解这个方程,得.·································································· 3分
当时,,去分母并解之,得······························· 4分
当时,,去分母并解之,得························ 5分
经检验,它们都是原方程的根.
原方程的根是,,.·························· 6分
22.解:
评分说明:每个图形中,画出剪切线给1分,画出所拼图形3分,其中一个用尺规画出剪切线的再给1分,共7分.
23.解:延长交于点··········································································· 1分
······································································· 2分
在Rt.······························································ 3分
····················································· 4分
在Rt.
························································ 5分
·································································································· 6分
答:这块土地的面积为m2·································································· 7分
评分说明:若过作交于,过作于,这样分割,
参照以上评分标准分步给分.
24.解:(1)所求函数关系式为
·············································································· 2分
即···················································································· 3分
(2)由于草莓必须在10天内售完
则有······················································································ 5分
解之,得····························································································· 7分
在函数中,
随的增大而减小····················································································· 8分
当时,有最大值31200(元)························································ 9分
,,
答:用4天时间运往省城批发,6天时间在本地零售.(回答销量也可)才使获利
润最大,最大利润为31200元.················ 10分
25.解:(1)猜想:······················· 1分
证明:连结
分别切于两点
······································· 2分
又
·································································································· 3分
(2)连结.··························································································· 4分
在和中,
是直径,
又············································ 5分
··················· 6分
(3)在,
,.
,··········································································· 7分
,.··············································· 8分
又,
····························································································· 9分
解之,得.即的值分别为.
······················································································································ 11分
26.(1)
;
的度数的度数.
评分说明:以上八类结论,写出一类中的一个结论给1分,同类中多写的结论不再
给分,最高不超过4分.
(2)的长是关于的方程的两根.
又是直径,且,
.
.
即.···················· 5分
,解之,得.
.······································································ 6分
将代入原方程,得
解之,得,
··································································· 7分
过作轴于,则.
.即.·········································· 8分
抛物线顶点为设抛物线的解析式为.
将点坐标代入,得.所求抛物线解析式为.················ 9分
(3)抛物线上存在点,使得是以为直角边的直角三角形.
①当时,点必须在的延长线上,设直线的解析式为
.
则...························································ 10分
解方程组 得 (即为点,舍去)
······················································································································ 11分
②当为直角时,延长交于,连结,则为直径,
四边形为内接矩形...
过作轴于,则..
可求得直线的解析式为····················································· 12分
解方程组(即为点,舍去)
点的坐标为或··············································· 13分