株洲市2007年初中毕业学业考试试卷
数 学
考生注意:1.本卷总分为100分,考试时量为120分钟;
2.全卷共有25道题,共8页. 一、填空题(本题共有8个小题,每小题3分,共计24分) 1.2的相反数是 .
2.如图,已知AB∥CD,直线MN分别交AB,CD于E,F,∠MFD=50o,EG平分 ∠MEB,那么∠MEG的大小是______________度. A
E
M
G
40
C B
B C 40
B
D
50
C F N
第2题图
D A
A
40
D
第8题图
第5题图
3.若2x3ym与3xny2 是同类项,则mn____________.
4.针对药品市场价格不规范的现象,药监部门对部分药品的价格进行了调整.已知某药品 原价为a元,经过调整后,药价降低了60%,则该药品调整后的价格为_____________元. 5.如图,小明在操场上从A点出发,沿直线前进10米后向左转40o,再沿直线前进10米后,又向左转40o,„„,照这样走下去,他第一次回到出发地A点时,一共走了 米. 6.已知△ABC的三条边长分别为6cm,8cm,10cm,则这个三角形的外接圆的面积为__________cm2.(结果用含的代数式表示)
7.甲、乙两人玩猜数字游戏,先由甲心中任想一个数字,记为a,再由乙猜甲刚才所想数字,把乙所猜数字记为b,且a,b分别取数字0,1,2,3,若a,b满足ab≤1,则称甲、乙两人“心有灵犀”.现任意找两人玩这个游戏,得出他们“心有灵犀”的概率为 . 8.如图,将边长为3的正方形ABCD绕点A逆时针方向旋转30o后得到正方形ABCD,则图中阴影部分的面积为 ____________平方单位.
二、选择题(每小题有且只有一个正确答案,请将正确答案的选项代号填入下面表格中,每小题3分,共计30分) 9.下列各式中错误的是( ) ..A.1 B.20111 C.sin30 D.832 2210.二元一次方程组xy3的解是( )
2xy0B.A.x1
y2
x1
y2
C.x1
y2
D.x2
y111.一个几何体的三视图如下图所示,
主视图
左视图
俯视图
那么这个几何体是( )
A.
B.
C.
D.
12.现有2cm,4cm,5cm,8cm长的四根木棒,任意选取三根组成一个三角形,那么可以组成三角形的个数为( )
A.1个 B.2个 C.3个 D.4个
x5x213.已知两圆的半径分别是5和6,圆心距x满足不等式组,则两圆的 28x413x14位置关系是( )
A.内切 B.外切 C.相交 D.外离
14.某种细胞开始有2个,1小时后成4个并死去1个,2小时后成6个并死去1个,3小时后成10个并死去1个,„„,按此规律,5小时后细胞存活的个数是( ) A.31 B.33 C.35 D.37 15.如图,一次函数yxb与反比例函数y
k
的图象相交于A,B两点,若已知一个交x
点为A(2,1),则另一个交点B的坐标为( )
1) B.(2,1) C.(1,2) D.(1,2) A.(2,
3 2 1 人数y 20A 121 2 3 3 2 1 O
B 1 2 x 8623 第15题图
跳绳羽毛球篮球乒乓球踢毽子其它项目第16题图16.“阳光体育”运动在我市轰轰烈烈开展,为了解同学们最喜爱的阳光体育运动项目,小王对本班50名同学进行了跳绳,羽毛球,篮球,乒乓球,踢毽子等运动项目最喜爱人数的调查,并根据调查结果绘制了如上的人数分布直方图,若将其转化为扇形统计图,那么最喜爱打篮球的人数所在扇形区域的圆心角的度数为( )
A.120o B.144o C.180o D.72o
17.如图,矩形ABCD中,AB=3,AD=4,动点P沿A→B→C→D的路线由A点运动到D点,则△APD的面积S是动点P运动的路程x的函数,这个函数的大致图象可能是( )
A B P
0 C. 10 x 0 D. 10 x C D 0 A.
S 6 S 6 10 x 0 B. 10 x S 6 S 6 18.某同学5次上学途中所花的时间(单位:分钟)分别为x,y,10,11,9,已知这组数据的平均数为10,方差为2,则xy的值为( )
A.1 B.2 C.3 D.4
三、解答题(本大题共7个小题,要求写出详细的演算过程或推理过程,否则不予给分,共计46分)
19.(本题满分6分,每小题3分) (1)计算:(12112x)24 (2)解分式方程:2 234x1x120.(本题满分6分)
a2b2已知x1是一元二次方程axbx400的一个解,且ab,求的值.
2a2b221.(本题满分6分)
某渔船上的渔民在A处观测到灯塔M在北偏东60o方向处,这艘渔船以每小时28海里的速度向正东方向航行,半小时后到达B处,在B处观测到灯塔M在北偏东30o方向处.问B处与灯塔M的距离是多少海里?
22.(本题满分6分)
如图,在四边形ABCD中,AB=CD,M,N,P,Q分别是AD,BC,BD,AC的中点. 求证:MN与PQ互相垂直平分.
23.(本题满分6分)
一枚质量均匀的正方体骰子,六个面上分别标有数字1,2,3,4,5,6,连续抛掷两次. (1)用列表法或树状图表示出朝上的面上的数字所有可能出现的结果;
(2)记两次朝上的面上的数字分别为p,q,若把p,q分别作为点A的横坐标和纵坐标, 求点A(p,q)在函数y
B
N
C
P Q
A
M
D
A 北
M
60 30
B
东
12的图象上的概率. x
24.(本题满分7分)
有一座抛物线型拱桥,其水面宽AB为18米,拱顶O离水面AB的距离OM为8米,货船在水面上的部分的横断面是矩形CDEF,如图建立平面直角坐标系. (1)求此抛物线的解析式;
(2)如果限定矩形的长CD为9米,那么矩形的高DE不能超过多少米,才能使船通过拱桥?
(3)若设EF=a,请将矩形CDEF的面积S用含a的代数式表示,并指出a的取值范围. y O
x E F
25.(本题满分9分)
已知Rt△ABC,∠ACB=90o,AC=4,BC=3,CD⊥AB于点D,以D为坐标原点,CD所在直线为y轴建立如图所示平面直角坐标系. (1)求A,B,C三点的坐标;
(2)若⊙O1,⊙O2分别为△ACD,△BCD的内切圆,求直线O1O2的解析式;
(3)若直线O1O2分别交AC,BC于点M,N,判断CM与CN的大小关系,并证明你的结论.
A M y C B C M D A O1 O2 D N B x
株洲市2007年初中毕业学业考试试卷
数学参及评分标准
一、填空题: 1.2 2.25 二、选择题: 题 次 答 案 9 D 10 A 11 C 12 B 13 C 14 B 15 C 16 B 17 A 18 D 3.5
4.0.4a
5.90 6.25 7.
5 8.33 8三、解答题: 19.(1)原式121····················································································· 1分 24 ·
234 12166 ································································································· 2分 2 ················································································································· 3分 (2)去分母,得:x12x(x1)2(x21) ·································································· 1分 解之得:x3 ·············································································································· 2分 经检验,x3是原方程的根. ···················································································· 3分 20.由x1是一元二次方程axbx400的一个解,得:ab40 ······················ 3分
2a2b2(ab)(ab)ab 又ab,得:··············································· 6分 20 ·
2a2b2(ab)221.解法一:过点M作直线AB的垂线MC,垂足为C,设MCx,在Rt△AMC中,
AC3x;在Rt△BMC中,BC3······························································ 3分 x ·3 由于ACBCAB得:3x33x14,解得:x73,BCx7 33 在Rt△BMC中,BM2BC14 ············································································· 5分
答:灯塔B与渔船M的距离是14海里. ···································································· 6分
M30 · 解法二:如图,在△ABM中,MAB30,ABM120,······· 4分 B ABM,又AB14MB14 ············································································· 5分 答:略 ······························································································································ 6分
22.连结MP,PN,NQ,QM,
∥ PM AMMD,BPPD
111∥AB,MQDC,PM ∥NQ AB;同理NQ 222 四边形MPNQ是平行四边形 ····················································································· 3分
又
ABDC,PMMQ
平行四边形MPNQ是菱形 ························································································· 5分 MN与PQ互相垂直平分 ··························································································· 6分 23.(1)列表法:··················································································································· 3分 第一次 第二次 1 2 3 4 5 6 1 2 3 4 5 6 (11), (2,1) (2,2) (31), (3,2) (4,1) (4,2) (51), (5,2) (6,1) (6,2) (1,2) (1,3) (1,4) (1,5) (1,6) (2,3) (2,4) (2,5) (2,6) (3,3) (3,4) (3,5) (3,6) (4,3) (4,4) (4,5) (4,6) (5,3) (5,4) (5,5) (5,6) (6,3) (6,4) (6,5) (6,6) 6)(34)(43)(62)在函数y(2)因为有四点(2,,,,,,, 所求概率为P24.(1)y12的图象上, ···································· 5分 x41 ······························································································ 6分 36982x(9≤x≤9) ······················································································· 2分 81 (2)CD9
989 点E的横坐标为,则点E的纵坐标为2
2812 点E的坐标为,2,因此要使货船能通过拱桥,则货船最大高度不能超过
292826(米) ·············································································································· 5分
(3)由EFa,则E点坐标为 S矩形CDEFEFED8a
2221a,a2,此时ED8a28a2
818181223a (0a18)· ···················································· 7分 81
25.(1)在Rt△ABC中,CD⊥AB
∽△AC BAC2ADAB,AD △ADC16 5912 同理DB,CD
55 Ay C 16912······ 3分 ,0,B,0,C0 ·,555M E (2)设则有S△ADCO1的半径为r1,O2的半径为r2,
A O1 D O2 N B x 11ADCD(ADCDAC)r1 22ADCD43 同理r2 r1ADCDAC55 O1,,O2, ···························································································· 4分 由此可求得直线O1O2的解析式为:y44553355124x ··················································· 5分 735312x, 45 (3)CM与CN的大小关系是相等. ·········································································· 6分 证明如下:法一:由(1)易得直线AC的解析式为:y 联立直线O1O2的解析式,求得点M的纵坐标为yM 过点M作ME⊥y轴于点E,
24, ····································· 7分 2536CECM,由Rt△CME∽Rt△CAD,得,
25CDCA1212 解得:CM 同理CN,CMCN······················································· 9分
55 CECDDE法二:由
O1D2r14ACRt△O1O2D∽Rt△ABC O2D2r23BC O2O1DBAC ····································································································· 8分 由此可推理:CMNO1DA45,··················· 9分 CNM45,CMCN ·
本答案仅供参考,若有其他解法,请参照本评分标准评分