二0一0年济南市初三年级学业水平考试
数 学 试 题
第Ⅰ卷(选择题 共48分)
一、选择题(本大题共12个小题,每小题4分,共48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.) 1.2+(-2)的值是 C A.-4
B.
14
C.0 D.4
2.一组数据0、1、2、2、3、1、3、3的众数是D A.0 B.1 C.2 D.3
3.图中的几何体是由7个大小相同的小正方体组成的,该几何体的俯视图为D
第3题图
D. C. B. A.
4.作为历史上第一个正式提出“低碳世博”理念的世博会,上海世博会从一开始就确定以“低碳、和谐、可持续发展的城市”为主题.如今在世博场馆和周边共运行着一千多辆新能源汽车,为目前世界上规模最大的新能源汽车示范运行,预计将减少温室气体排放约28400吨.将28400吨用科学记数法表示为B A.0.284×105 吨 B.2.84×104吨 C.28.4×103吨 D.284×102吨 5.二元一次方程组
xy4xy2
第4题图
的解是D
A.
x3y7
B.
x1y1
C.
x7y3
D.
x3y1
6.下列各选项的运算结果正确的是B
20
15 C.x6x2x3 D.(ab)2a2b2
7.在一次体育课上,体育老师对九年级一班的40名同学进行了10 跳远项目的测试,测试所得分数及相应的人数如图所示,则这5
0 试的平均分为 A.分 B.
35
354
人数(人)
A.(2x2)38x6 B.5a2b2a2b3
立定
次测
6分 8分 10分
第7题图
分数
分 C.
403
分 D.8分
8.一次函数y2x1的图象经过哪几个象限B A.一、二、三象限 C.一、三、四象限
B.一、二、四象限 D.二、三、四象限
D
M、N分别
为
9.如图所示,正方形ABCD中,对角线AC、BD交于点O,点
第9题图
OB、OC的中点,则cos∠OMN的值为C
A.
12
B
2
C2
D.1
10.二次函数yx2x2的图象如图所示,则函数值y<0时
x的取值范围是
A.x<-1
B.x>2
C.-1<x<2
第10题图 D.x<-1或x>2
11.观察下列图形及图形所对应的算式,根据你发现的规律计算1+8+16+24+……+8n(n是正整数)的结果为
……
⑴ ⑶ ⑵
1+8+16+24=?1+8=?1+8+16=?
A.(2n1)2 B.(2n1)2 C.(n2)2 D.
n2 12.如图所示,矩形ABCD中,AB=4,BC=,点E是折线段A-
第11题图
D
D-C上的一个动点(点E与点A不重合),点P是点A关于BE
的对称点.在点E运动的过程中,使△PCB为等腰三角形的点E的位置共有
A.2个 B.3个 C.4个 D.5个 绝密★启用前
济南市2010年初三年级学业水平考试
数 学 试 题
注意事项:
1.第Ⅱ卷共6页.用蓝、黑色钢笔或圆珠笔直接答在考试卷上. 2.答卷前将密封线内的项目填写清楚.
第Ⅱ卷(非选择题 共72分) 第12题图
二、填空题(本大题共5个小题,每小题3分,共15分.把答案填在题
中的横线上.) 2
13.分解因式:x2x1 14.如图所示,△DEF是△ABC沿水平方向向右平移后的对
应图形,若∠B=31°,∠C=79°,则∠D的度数是 度.
C E 15.解方程
2x1
32x3
的结果是 .
第14
题图
1x
16.如图所示,点A是双曲线y在第二象限的分支上的任意一点,点B、C、D分别是点A关于x轴、
原点、y轴的对称点,则四边形ABCD的面积是 .
17.如图所示,△ABC的三个顶点的坐标分别为A(-1,3)、B (-2,-2)、C (4,-2),则
△ABC外接圆半径的长度为 .
三、解答题(本大题共7个小题,共57分.解答应写出文字说明、证明过程或演算步骤.)
18.(本小题满分7分)
⑴解不等式组:
x2x2x≤4
⑵如图所示,在梯形ABCD中,BC∥AD,AB=DC,点M是AD的中点. 求证:BM=CM.
∵BC∥AD,AB=DC,
∴∠BAM=∠CDM, ···································
···················分 ∵点M是AD的中点,
∴AM=DM, ················································M
第18题图 3分 ∴△ABM≌△DCM, ································································· ∴BM=CM.
19.(本小题满分7分)
(3)0
⑵如图所示,△ABC中,∠C=90°,∠B=30°,AD是△ABC的角平分线,若AC 求线段AD的长.
第19题图
20.(本小题满分8分)
如图所示,有一个可以自由转动的圆形转盘,被平均分成四个扇形,四个扇形内分别标有数字1、2、-3、-4.若将转盘转动两次,每一次停止转动后,指针指向的扇形内的数字分别记为a、b(若指针恰好指在分界线上,则该次不计,重新转动一次,直至指针落在扇形内).
请你用列表法或树状图求a与 b的乘积等于2的概率.
21.(本小题满分8分) 第20题图
如图所示,某幼儿园有一道长为16米的墙,计划用32米长的围栏靠墙围成一个面积为120平方米的矩形草坪ABCD.求该矩形草坪BC边的长.
第21题图
22.(
本小题满分9分)
如图所示,菱形ABCD的顶点A、B在x轴上,点A在点B的左侧,点D在y轴的正半轴上,∠BAD=60°,点A的坐标为(-2,0).
⑴求线段AD所在直线的函数表达式.
⑵动点P从点A出发,以每秒1→B→A的顺
序在菱形的边上匀速运动一周,设运动时间为t以点P为圆心、以1为半径的圆与对角线AC相切?
第22题图
23.(本小题满分9分)
已知:△ABC是任意三角形.
⑴如图1所示,点M、P、N分别是边AB、BC、CA的中点.求证:∠MPN=∠A
. ⑵如图2所示,点M、N分别在边AB、AC上,且
AMAB
13
,
ANAC
13
,点P1、P2是边BC的三等分
点,你认为∠MP1N+∠MP2N=∠A是否正确?请说明你的理由.
⑶如图3所示,点M、N分别在边AB、AC上,且
AMAB
12010
,
ANAC
12010
,点P1、P2、……、P2009
是边BC的2010等分点,则∠MP1N+∠MP2N+……+∠MP2009N=____________. (请直接将该小问的答案写在横线上.) A A N
N
N
……
C C 1 2 2009C 1 2 第23题图2 第23题图3 第23题图1
24.(本小题满分9分)
如图所示,抛物线yx22x3与x轴交于A、B两点,直线BD的函数表达式为y抛物线的对称轴l与直线BD交于点C、与x轴交于点E. ⑴求A、B、C三个点的坐标.
⑵点P为线段AB上的一个动点(与点A、点B不重合),以点A为圆心、以AP为半径的圆弧与线段AC交于点M,以点B为圆心、以BP为半径的圆弧与线段BC交于点N,分别连接AN、BM、MN.
①求证:AN=BM.
②在点P运动的过程中,四边形AMNB的面积有最大值还是有最小值?并求出该最大值或最小值.
济南市2010年初三年级学业水平考试
数学试题参考答案及评分标准
13. (x1)2 14. 70 15. x9 16. 4 17. 三、解答题 18.(1)解:
x2>x2x≤4
① ②
解不等式①,得x>1, ·································································· 1分 解不等式②,得x≥-2, ··································································· 2分 ∴不等式组的解集为x>1. ···································································· 3分 (2) 证明:∵BC∥AD,AB=DC,
∴∠BAM=∠CDM, ··································································· 1分 ∵点M是AD的中点,
∴AM=DM, ··············································································· 2分
∴△ABM≌△DCM, ·········································
························ 3分 ∴BM=CM. ··············································
·································· 4分 19.(1)解:原式(3)
·····················
······································ 1分
2+1 ················································································ 2分
-1 ··················································································· 3分
(2)解:∵△ABC中,∠C=90º,∠B=30º,
∴∠BAC=60º,
∵AD是△ABC的角平分线,
∴∠CAD=30º, ···········
········
·························································· 1分 ∴在Rt△ADC中,AD
ACcos30
················································· 2分 ·······················
························· 3分
=2 . ························································ 4分
20.解:a与b
·················································································································· 6分 总共有16种结果,每种结果出现的可能性相同,其中ab=2的结果有2种, ··························································································································· 7分 ∴a与 b的乘积等于2的概率是. ·························································· 8分
81
21.解:设BC边的长为x米,根据题意得 ··················································· 1分 x32x2
120
, ················································································· 4分
解得:x112,x220, ··········································································· 6分
∵20>16,
∴x220不合题意,舍去, ·················································
··············
·· 7分
答:该矩形草坪BC边的长为12米. ··············································· 8分 22. 解:⑴∵点A的坐标为(-2,0),∠BAD=60°
,∠AOD=90°,
∴OD=OA·tan60°=,
∴点
D的坐标为(0
,, ··············
·····
········································· 1分 设直线AD的函数表达式为ykxb,
2kb0
bk,解得
b
∴直线AD的函数表达式为y. ······································· 3分 ⑵∵四边形ABCD是菱形,
∴∠DCB=∠BAD=60°, ∴∠1=∠2=∠3=∠4=30°, AD=DC=CB=BA=4, ········································································· 5分 如图所示:
①点P在AD上与AC相切时, AP1=2r=2, ∴t1=2. ·································································································· 6分
②点P在DC上与AC相切时,
CP2=2r=2,
∴AD+DP2=6, ∴t2=6. ······································ 7分 ③点P在BC上与AC相切时,
CP3=2r=2,
第22题图
∴AD+DC+CP3=10, ∴t3=10. ······································ 8分 ④点P在AB上与AC相切时, AP4=2r=2,
∴AD+DC+CB+BP4=14, ∴t4=14,
∴当t=2、6、10、14时,以点P为圆心、以1为半径的圆与对角线AC相切. ··························································· 9分
23. ⑴证明:∵点M、P、N分别是AB、BC、CA的中点, ∴线段MP、PN是△ABC的中位线,
∴MP∥AN,PN∥AM, ··················· 1分
∴四边形AMPN是平行四边形, ····· 2分
M
∴∠MPN=∠A. ···························· 3分
1 2 ⑵∠MP1N+∠MP2N=∠A正确. ··················· 4分
如图所示,连接MN, ···························· 5分 ∵
AMAB
ANAC
13
A N
,∠A=∠A,
B
P1 P2
C
∴△AMN∽△ABC, ∴∠AMN=∠B,
MNBC
13
第23题图
,
∴MN∥BC,MN=BC, ······················· 6分
3
1
∵点P1、P2是边BC的三等分点,
∴MN与BP1平行且相等,MN与P1P2平行且相等,MN与P2C平行且相等, ∴四边形MBP1N、MP1P2N、MP2CN都是平行四边形, ∴MB∥NP1,MP1∥NP2,MP2∥AC, ······································································ 7分 ∴∠MP1N=∠1,∠MP2N=∠2,∠BMP2=∠A, ∴∠MP1N+∠MP2N=∠1+∠2=∠BMP2=∠A. ····································································· 8分 ⑶∠A. ···················································· 9分
24.解:⑴令x2x30,
2
y
解得:x11,x23, ∴A(-1,0),B(3,0) ······························· 2分 ∵yx22x3=(x1)24, ∴抛物线的对称轴为直线x=1,
将x=1
代入y,得y
N
M
C
F
D
l
A O E P B x
第24题图
∴C(1,
. ··································· 3分 ⑵①在Rt△ACE中,tan∠CAE
=
CEAE
,
∴∠CAE=60º,
由抛物线的对称性可知l是线段AB的垂直平分线, ∴AC=BC,
∴△ABC为等边三角形, ·································································· 4分 ∴AB= BC =AC = 4,∠ABC=∠ACB= 60º, 又∵AM=AP,BN=BP, ∴BN = CM,
∴△ABN≌△BCM, ∴AN=BM. ···························································································· 5分 ②四边形AMNB的面积有最小值. ··················································· 6分 设AP=m,四边形AMNB的面积为S, 由①可知AB= BC= 4,BN = CM=BP,S△ABC
4
×42
=
∴CM=BN= BP=4-m,CN=m, 过M作MF⊥BC,垂足为F, 则MF=MC•sin60º
=
1
21
(4m),
2
m)=
4
2
∴S△CMN=CNMF=m
2
2
, ························· 7分
∴S=S△ABC-S△CMN
=
4
2
4
2
)
m2) ············································································· 8分
∴m=2时,S取得最小值
·························································· 9分
二0一0年济南市初三年级学业水平考试
数 学 试 题
第Ⅰ卷(选择题 共48分)
一、选择题(本大题共12个小题,每小题4分,共48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.) 1.2+(-2)的值是 C A.-4
B.
14
C.0 D.4
2.一组数据0、1、2、2、3、1、3、3的众数是D A.0 B.1 C.2 D.3
3.图中的几何体是由7个大小相同的小正方体组成的,该几何体的俯视图为D
第3题图
D. C. B. A.
4.作为历史上第一个正式提出“低碳世博”理念的世博会,上海世博会从一开始就确定以“低碳、和谐、可持续发展的城市”为主题.如今在世博场馆和周边共运行着一千多辆新能源汽车,为目前世界上规模最大的新能源汽车示范运行,预计将减少温室气体排放约28400吨.将28400吨用科学记数法表示为B A.0.284×105 吨 B.2.84×104吨 C.28.4×103吨 D.284×102吨 5.二元一次方程组
xy4xy2
第4题图
的解是D
A.
x3y7
B.
x1y1
C.
x7y3
D.
x3y1
6.下列各选项的运算结果正确的是B
20
15 C.x6x2x3 D.(ab)2a2b2
7.在一次体育课上,体育老师对九年级一班的40名同学进行了10 跳远项目的测试,测试所得分数及相应的人数如图所示,则这5
0 试的平均分为 A.分 B.
35
354
人数(人)
A.(2x2)38x6 B.5a2b2a2b3
立定
次测
6分 8分 10分
第7题图
分数
分 C.
403
分 D.8分
8.一次函数y2x1的图象经过哪几个象限B A.一、二、三象限 C.一、三、四象限
B.一、二、四象限 D.二、三、四象限
D
M、N分别
为
9.如图所示,正方形ABCD中,对角线AC、BD交于点O,点
第9题图
OB、OC的中点,则cos∠OMN的值为C
A.
12
B
2
C2
D.1
10.二次函数yx2x2的图象如图所示,则函数值y<0时
x的取值范围是
A.x<-1
B.x>2
C.-1<x<2
第10题图 D.x<-1或x>2
11.观察下列图形及图形所对应的算式,根据你发现的规律计算1+8+16+24+……+8n(n是正整数)的结果为
……
⑴ ⑶ ⑵
1+8+16+24=?1+8=?1+8+16=?
A.(2n1)2 B.(2n1)2 C.(n2)2 D.
n2 12.如图所示,矩形ABCD中,AB=4,BC=,点E是折线段A-
第11题图
D
D-C上的一个动点(点E与点A不重合),点P是点A关于BE
的对称点.在点E运动的过程中,使△PCB为等腰三角形的点E的位置共有
A.2个 B.3个 C.4个 D.5个 绝密★启用前
济南市2010年初三年级学业水平考试
数 学 试 题
注意事项:
1.第Ⅱ卷共6页.用蓝、黑色钢笔或圆珠笔直接答在考试卷上. 2.答卷前将密封线内的项目填写清楚.
第Ⅱ卷(非选择题 共72分) 第12题图
二、填空题(本大题共5个小题,每小题3分,共15分.把答案填在题
中的横线上.) 2
13.分解因式:x2x1 14.如图所示,△DEF是△ABC沿水平方向向右平移后的对
应图形,若∠B=31°,∠C=79°,则∠D的度数是 度.
C E 15.解方程
2x1
32x3
的结果是 .
第14
题图
1x
16.如图所示,点A是双曲线y在第二象限的分支上的任意一点,点B、C、D分别是点A关于x轴、
原点、y轴的对称点,则四边形ABCD的面积是 .
17.如图所示,△ABC的三个顶点的坐标分别为A(-1,3)、B (-2,-2)、C (4,-2),则
△ABC外接圆半径的长度为 .
三、解答题(本大题共7个小题,共57分.解答应写出文字说明、证明过程或演算步骤.)
18.(本小题满分7分)
⑴解不等式组:
x2x2x≤4
⑵如图所示,在梯形ABCD中,BC∥AD,AB=DC,点M是AD的中点. 求证:BM=CM.
∵BC∥AD,AB=DC,
∴∠BAM=∠CDM, ···································
···················分 ∵点M是AD的中点,
∴AM=DM, ················································M
第18题图 3分 ∴△ABM≌△DCM, ································································· ∴BM=CM.
19.(本小题满分7分)
(3)0
⑵如图所示,△ABC中,∠C=90°,∠B=30°,AD是△ABC的角平分线,若AC 求线段AD的长.
第19题图
20.(本小题满分8分)
如图所示,有一个可以自由转动的圆形转盘,被平均分成四个扇形,四个扇形内分别标有数字1、2、-3、-4.若将转盘转动两次,每一次停止转动后,指针指向的扇形内的数字分别记为a、b(若指针恰好指在分界线上,则该次不计,重新转动一次,直至指针落在扇形内).
请你用列表法或树状图求a与 b的乘积等于2的概率.
21.(本小题满分8分) 第20题图
如图所示,某幼儿园有一道长为16米的墙,计划用32米长的围栏靠墙围成一个面积为120平方米的矩形草坪ABCD.求该矩形草坪BC边的长.
第21题图
22.(
本小题满分9分)
如图所示,菱形ABCD的顶点A、B在x轴上,点A在点B的左侧,点D在y轴的正半轴上,∠BAD=60°,点A的坐标为(-2,0).
⑴求线段AD所在直线的函数表达式.
⑵动点P从点A出发,以每秒1→B→A的顺
序在菱形的边上匀速运动一周,设运动时间为t以点P为圆心、以1为半径的圆与对角线AC相切?
第22题图
23.(本小题满分9分)
已知:△ABC是任意三角形.
⑴如图1所示,点M、P、N分别是边AB、BC、CA的中点.求证:∠MPN=∠A
. ⑵如图2所示,点M、N分别在边AB、AC上,且
AMAB
13
,
ANAC
13
,点P1、P2是边BC的三等分
点,你认为∠MP1N+∠MP2N=∠A是否正确?请说明你的理由.
⑶如图3所示,点M、N分别在边AB、AC上,且
AMAB
12010
,
ANAC
12010
,点P1、P2、……、P2009
是边BC的2010等分点,则∠MP1N+∠MP2N+……+∠MP2009N=____________. (请直接将该小问的答案写在横线上.) A A N
N
N
……
C C 1 2 2009C 1 2 第23题图2 第23题图3 第23题图1
24.(本小题满分9分)
如图所示,抛物线yx22x3与x轴交于A、B两点,直线BD的函数表达式为y抛物线的对称轴l与直线BD交于点C、与x轴交于点E. ⑴求A、B、C三个点的坐标.
⑵点P为线段AB上的一个动点(与点A、点B不重合),以点A为圆心、以AP为半径的圆弧与线段AC交于点M,以点B为圆心、以BP为半径的圆弧与线段BC交于点N,分别连接AN、BM、MN.
①求证:AN=BM.
②在点P运动的过程中,四边形AMNB的面积有最大值还是有最小值?并求出该最大值或最小值.
济南市2010年初三年级学业水平考试
数学试题参考答案及评分标准
13. (x1)2 14. 70 15. x9 16. 4 17. 三、解答题 18.(1)解:
x2>x2x≤4
① ②
解不等式①,得x>1, ·································································· 1分 解不等式②,得x≥-2, ··································································· 2分 ∴不等式组的解集为x>1. ···································································· 3分 (2) 证明:∵BC∥AD,AB=DC,
∴∠BAM=∠CDM, ··································································· 1分 ∵点M是AD的中点,
∴AM=DM, ··············································································· 2分
∴△ABM≌△DCM, ·········································
························ 3分 ∴BM=CM. ··············································
·································· 4分 19.(1)解:原式(3)
·····················
······································ 1分
2+1 ················································································ 2分
-1 ··················································································· 3分
(2)解:∵△ABC中,∠C=90º,∠B=30º,
∴∠BAC=60º,
∵AD是△ABC的角平分线,
∴∠CAD=30º, ···········
········
·························································· 1分 ∴在Rt△ADC中,AD
ACcos30
················································· 2分 ·······················
························· 3分
=2 . ························································ 4分
20.解:a与b
·················································································································· 6分 总共有16种结果,每种结果出现的可能性相同,其中ab=2的结果有2种, ··························································································································· 7分 ∴a与 b的乘积等于2的概率是. ·························································· 8分
81
21.解:设BC边的长为x米,根据题意得 ··················································· 1分 x32x2
120
, ················································································· 4分
解得:x112,x220, ··········································································· 6分
∵20>16,
∴x220不合题意,舍去, ·················································
··············
·· 7分
答:该矩形草坪BC边的长为12米. ··············································· 8分 22. 解:⑴∵点A的坐标为(-2,0),∠BAD=60°
,∠AOD=90°,
∴OD=OA·tan60°=,
∴点
D的坐标为(0
,, ··············
·····
········································· 1分 设直线AD的函数表达式为ykxb,
2kb0
bk,解得
b
∴直线AD的函数表达式为y. ······································· 3分 ⑵∵四边形ABCD是菱形,
∴∠DCB=∠BAD=60°, ∴∠1=∠2=∠3=∠4=30°, AD=DC=CB=BA=4, ········································································· 5分 如图所示:
①点P在AD上与AC相切时, AP1=2r=2, ∴t1=2. ·································································································· 6分
②点P在DC上与AC相切时,
CP2=2r=2,
∴AD+DP2=6, ∴t2=6. ······································ 7分 ③点P在BC上与AC相切时,
CP3=2r=2,
第22题图
∴AD+DC+CP3=10, ∴t3=10. ······································ 8分 ④点P在AB上与AC相切时, AP4=2r=2,
∴AD+DC+CB+BP4=14, ∴t4=14,
∴当t=2、6、10、14时,以点P为圆心、以1为半径的圆与对角线AC相切. ··························································· 9分
23. ⑴证明:∵点M、P、N分别是AB、BC、CA的中点, ∴线段MP、PN是△ABC的中位线,
∴MP∥AN,PN∥AM, ··················· 1分
∴四边形AMPN是平行四边形, ····· 2分
M
∴∠MPN=∠A. ···························· 3分
1 2 ⑵∠MP1N+∠MP2N=∠A正确. ··················· 4分
如图所示,连接MN, ···························· 5分 ∵
AMAB
ANAC
13
A N
,∠A=∠A,
B
P1 P2
C
∴△AMN∽△ABC, ∴∠AMN=∠B,
MNBC
13
第23题图
,
∴MN∥BC,MN=BC, ······················· 6分
3
1
∵点P1、P2是边BC的三等分点,
∴MN与BP1平行且相等,MN与P1P2平行且相等,MN与P2C平行且相等, ∴四边形MBP1N、MP1P2N、MP2CN都是平行四边形, ∴MB∥NP1,MP1∥NP2,MP2∥AC, ······································································ 7分 ∴∠MP1N=∠1,∠MP2N=∠2,∠BMP2=∠A, ∴∠MP1N+∠MP2N=∠1+∠2=∠BMP2=∠A. ····································································· 8分 ⑶∠A. ···················································· 9分
24.解:⑴令x2x30,
2
y
解得:x11,x23, ∴A(-1,0),B(3,0) ······························· 2分 ∵yx22x3=(x1)24, ∴抛物线的对称轴为直线x=1,
将x=1
代入y,得y
N
M
C
F
D
l
A O E P B x
第24题图
∴C(1,
. ··································· 3分 ⑵①在Rt△ACE中,tan∠CAE
=
CEAE
,
∴∠CAE=60º,
由抛物线的对称性可知l是线段AB的垂直平分线, ∴AC=BC,
∴△ABC为等边三角形, ·································································· 4分 ∴AB= BC =AC = 4,∠ABC=∠ACB= 60º, 又∵AM=AP,BN=BP, ∴BN = CM,
∴△ABN≌△BCM, ∴AN=BM. ···························································································· 5分 ②四边形AMNB的面积有最小值. ··················································· 6分 设AP=m,四边形AMNB的面积为S, 由①可知AB= BC= 4,BN = CM=BP,S△ABC
4
×42
=
∴CM=BN= BP=4-m,CN=m, 过M作MF⊥BC,垂足为F, 则MF=MC•sin60º
=
1
21
(4m),
2
m)=
4
2
∴S△CMN=CNMF=m
2
2
, ························· 7分
∴S=S△ABC-S△CMN
=
4
2
4
2
)
m2) ············································································· 8分
∴m=2时,S取得最小值
·························································· 9分