logo资料库

2009年湖南省湘潭市中考数学真题及答案.doc

第1页 / 共8页
第2页 / 共8页
第3页 / 共8页
第4页 / 共8页
第5页 / 共8页
第6页 / 共8页
第7页 / 共8页
第8页 / 共8页
资料共8页,全文预览结束
2009 年湖南省湘潭市中考数学真题及答案 考试时量:120 分钟 满分:120 分 新爱的同学,你好!今天是展示你的才能的时候了,请你仔细审题,认真答题,发挥自己的正常水平, 轻松一点,相信自己的实力! 考生注意:本试卷分试题卷和答题卡两部分,全卷共三道大题,26 道小题;请考生将解答过程全部填 (涂)或写在答题卡上,写在试题卷上无效,考试结束后,将试题卷和答题卡一并上交. 一、选择题(本题共 8 个小题,每小题有且只有一个正确答案,请将正确答案的选项代号涂在答题卡相应 的位置上,每小题 3 分,满分 24 分) 1.下列判断中,你认为正确的是( ) A.0 的倒数是 0 B. 5 大于 2 D. 9 的值是 3 C. π 是有理数 2.一个正多边形的每个外角都是36°,这个正多边形是( A.正六边形 B.正八边形 C.正十边形 ) D.正十二边形 ) B. ) A O x  x 3 D. x ≤ 3 3.函数 x ≥ 3 x ≥ 50 D.100° 0 C. A  °,  中,自变量 x 的取值范围是( y A. 3 4.如图,点 A B C, , 在 O 上, 则 BOC 的度数为( A.130° B.50° C.65° 5.在 Rt ABC△ A.60° 6.同一时刻,身高 2.26m 的姚明在阳光下影长为 1.13m;小林浩在阳光下的影长为 0.64m,则小林浩的身 高为( A.1.28m 7.对于样本数据 1,2,3,2,2,以下判断:①平均数为 5;②中位数为 2;③众数为 2;④极差为 2.正 确的有( A.1 个 90 C  °,若 C.30° A  ,则 A 的度数是( ) B.2 个 (第 4 题图) B. 45° D.无法确定 D.0.32m B.1.13m C.0.64m C.3 个 D.4 个 sin 中, 1 2 B ) ) C 8.在同一直角坐标系中,二次函数 y 2 x y  与一次函数 2 x 的图象大致是( 2 y ) y y y 2 x o o x 2 o x  二、填空题(本题共 8 个小题,请将答案写在答题卡相应的位置上,每小题 3 分,满分 24 分) 9. 6.18 10.已知 y 是 x 的反比例函数,当 4 2 B x  时, 2 y  .则 y 与 x 的函数关系式是 的绝对值是 A . . C x o 2 D
, 中, AB AC . 11. ABC△ 则 B 的度数是 12.如图,天平盘中每个小球的重量用 x 克表示, 砝码每个 5 克,那么 x  A  °, 克. 36 13.已知 m n  , 5 mn  ,则 2 m n mn 3 2  . 中, D E F, , 分别是 AB BC AC 14.在等边三角形、正方形、矩形、菱形中,是轴对称图形但不是中心对称图形的是 15.如图, ABC△ 已知 DF 使 ADF 16.调查某小区内 30 户居民月人均收入情况,制成如下的频数分 布直方图,收入在 1200~1240 元的频数是 AB∥ ,请补充一个条件: . BC∥ , EF FEC , , 上的点, ≌△ △ . , A D . F (户) B E (第 15 题图) C 15 10 5 0 7 3 4 1 1 1120 1160 1200 1240 1280 1320 1360 元 (第 16 题图) 三、解答题(本大题共 10 个小题,解答应写出文字说明、证明过程或演算步骤,请将解答过程写在答题卡 相应的位置上,满分 72 分) 17.(本题满分 6 分) 计算: 4 2 tan 45  °  (π 0 6) . 18.(本题满分 6 分) 先化简,再求值: (2 x  2 y )  (2 x  y )(2 x  y ) 4  xy ;其中 2009 x  , y   . 1 19.(本题满分 6 分) 某物体的三视图如右图: (1)此物体是 (2)求此物体的全面积. 体; 20 20 40 40 20 主视图 左视图 俯视图
20.(本题满分 6 分) 解不等式组,并将解集在数轴上表示出来. x x        5 3 4 6 x  3 ① ② 21.(本题满分 6 分) 如图, B C E, , 是同一直线上的三个点,四边形 ABCD 与四边形CEFG 都是正方形,连结 BG DE, . (1)观察图形,猜想 BG 与 DE 之间的大小关系,并证明你的结论; (2)若延长 BG 交 DE 于点 H ,求证: BH DE . A D G H B C F E 22.(本题满分 6 分) 解方程: 40 x  40 2 x   1 . 23.(本题满分 8 分) 小明练习 100 米短跑,训练时间与 100 米短跑成绩记录如下: 时间(月) 1 2 3 成绩(秒) 15.6 15.4 15.2 4 15 (1)请你为小明的 100 米短跑成绩 y (秒)与训练时间 x (月)的关系建立函数模型; (2)用所求出的函数解析式预测小明训练 6 个月的 100 米短跑成绩; (3)能用所求出的函数解析式预测小明训练 3 年的 100 米短跑成绩吗?为什么? 24.(本题满分 8 分) 小亮看到路边上有人设摊玩“有奖掷币”游戏,规则是:交 2 元钱可以玩一次掷硬币游戏,每次同时掷两 枚硬币,如果出现两枚硬币正面朝上,奖金 5 元;如果是其它情况,则没有奖金(每枚硬币落地只有正面 朝上和反面朝上两种情况).小亮拿不定主意究竟是玩还是不玩,请同学们帮帮忙! (1)求出中奖的概率; (2)如果有 100 人,每人玩一次这种游戏,大约有 人中奖,奖金共约是 元,设摊者约获利
元; (3)通过以上“有奖”游戏,你从中可得到什么启示? 25.(本题满分 10 分) 如图, AB 是 O 的直径,CD 是弦,CD AB (1)求证: ACE CBE ∽△ △ ; 于点 E , (2)若 AB  ,设OE x ( 0 8 x  ), 2CE 4 y ,请求出 y 关于 x 的函数解析式; (3)探究:当 x 为何值时, tan D  3 3 . A EO C D B 26.(本题满分 10 分) 如图,在平面直角坐标系中,四边形OABC 为矩形, OP 绕点 P 逆时针方向旋转90°交直线 BC 于点Q ; OA  , 3 OC  , P 为直线 AB 上一动点,将直线 4 (1)当点 P 在线段 AB 上运动(不与 A B, 重合)时,求证:OA BQ AP BP  ;   (2)在(1)成立的条件下,设点 P 的横坐标为 m ,线段CQ 的长度为l ,求出l 关于 m 的函数解析式,并 判断l 是否存在最小值,若存在,请求出最小值;若不存在,请说明理由; (3)直线 AB 上是否存在点 P ,使 POQ△ 为等腰三角形,若存在,请求出点 P 的坐标;若不存在,请说 明理由. y A P B Q 湘潭市 2009 年初中毕业学业考试 数学试卷参考答案及评分标准 O C x 一、选择题(本题共 8 个小题,每小题 3 分,满分 24 分) 1.B 二、填空题(本题共 8 个小题,每小题 3 分,满分 24 分) 5.C 7.D 6.A 2.C 3.B 4.D 8.C
9.6.18 10. y  11. 72° 12.10 13.15 14.等边三角线 8 x 或 AD FE 或 F 为 AC 中点或 DF 为中位线或 EF 为中位线或 DE AC∥ 等 或 DF EC 15. AF FC 16.14 三、解答题(本大题共 10 个小题,满分 72 分) 17.(本题满分 6 分) 解: 4 2 tan 45   ° (π 0 6) 2 2 1 1 2 2 1     ··································································································4 分    ····································································································· 5 分 1 ··············································································································· 6 分 18.(本题满分 6 分) 解: (2 x  2 y )  (2 x  y )(2 x  y ) 4  xy  2 4 x  4 xy  2 y  2 (4 x  2 y ) 4  xy ··································································· 3 分  2 4 x  4 xy  2 y  2 4 x  2 y  4 xy 22y ··········································································································· 4 分 当 2009 x  , y   时, 1 原式 22 y    ··················································································· 6 分 2 1 2 19.(本题满分 6 分) (1)圆柱······································································································ 2 分 (2) 20π 40 2 π 10     2 ··············································································· 4 分 1000π  20.(本题满分 6 分) ······································································································· 6 分 2 3x ·····················································································1 分 x   ···············································································2 分 解:不等式①的解集 不等式②的解集 3x  ·······················································································4 分 不等式组的解集 2    ················································································ 5 分 在数轴上表示(略)·························································································6 分 21.(本题满分 6 分) (1)猜想: BG DE BC DC    CG CE  BCG ≌△ (2)在 BCG△ 由(1)得 CBG  DGH     中   ·············································································· 4 分 ··························································································· 5 分 (SAS)············································································ 3 分 DCE 与 DHG△ CDE  °  ° 90 BCG DCE CGB DHB   BCG 90 △
 BH DE  22.(本题满分 6 分) ·································································································· 6 分 解:方程两边同乘以 ( x x  ,得·······································································1 分 2) 40( x  2) 40  x  ( x x  2) ················································································2 分  2 x 80 0 整理得 2 x  ···················································································· 3 分 10 x   或 8x  ···························································································5 分 x   , 8x  都是原方程的根.···························································· 6 分 经检验 23.(本题满分 8 分) 10 (1)设 y  kx b  依题意得···············································································1 分 15.6   15.4  k b   2 k b   ······························································································· 2 分 解答 ······························································································· 3 分 的概率是 ;································································································· 3 分 (2)25,125,75····························································································6 分 (3)略(只要有理就行)················································································· 8 分 25.(本题满分 10 分) (1)证明: AB 为 O 直径, 又CD AB A    △ (2)  A    , Rt  △ CBE ∽△  ························································ 3 分  90  ° Rt ∽ △ , ECB ACE AO OE OB OE ACE ACE  °即 AE BE  ° 90 即 2 CE CBE ACE BCE ACB    ( 90   )(  )  )(4  x ) 16   x 2 ············································································ 6 分  AE CE CE EB x y    (4 (3)解法一:  tan D  3 3 即 tan A  3 3 0.2 k      15.8 b 0.2  x 1 4    y 15.8 ·························································································· 4 分 (2)当 6 x  时, y   0.2 6 15.8   ································································· 5 分 14.6  ·········································································································· 6 分 (3)不能······································································································ 7 分 略(理由合理)·······························································································8 分 24.(本题满分 8 分) (1)解:掷两枚硬币出现的情况是(正,正)、(正,反)、(反,正)、(反,反),故出现两枚硬币都朝上
 CE AE  3 3 则 2 2 CE AE  即 1 3 16  (4  2 x ) x 2  1 3 解得 2 x  或 x   (舍去) 4 故当 2 x  时, tan D  3 3 ···········································································10 分 解法二:  tan   D 3 3  BE BE DE CE   4 x  16 x  2 即 3 3  4 x  16 x  2   1 3 (4  16  2 ) x 2 x 解得 2 x  或 4 x  (舍去) 故当 2 x  时, tan D  26.(本题满分 10 分) 3 3 ···········································································10 分 (1)证明: PO PQ ,  APO   BPQ  °, 90 APO   AOP  °, 90  在 Rt AOP△    BPQ 中,  AOP △ AOP ∽△ BPQ ,则 (2) OA BP AP BP      AP BQ OA BP BQ  ,即   即OA BQ AP BP m m )  (4  3 ······································· 3 分 3    l 4 m m  3 2  1 3 2 ( m  4 m  4)   5 3 1 3 ( m  2) 2  5 3 5 3 当 2m  时, l 有最小值 (3)解法一 △ POQ 是等腰三角形 .·········································································· 6 分 ①若 P 在线段 AB 上, OPQ  ° 90   PO PQ ,又 AOP △ ∽△ BPQ , △ AOP ≌△ BPQ   PB AO ,即3 4 m   , 1m  ,即 P 点坐标 (1 3), ········································ 8 分 ②若 P 在线段 AB 的延长线上, PQ 交CB 的延长线于Q , PO PQ ,
又 △ AOP ∽△ BPQ , △ AOP ≌△ BPQ ,  AO PB  ,即3 4m  ,即 P 点的坐标 (7 3), , P 故存在 1 (1 3) P,, , 使 POQ△ (7 3) 2 为等腰三角形.··············································· 10 分 解法二 POQ△ 是等腰三角形   PO PQ , 即 2 PA  2 AO  2 PB  2 BQ ·············································································· 7 分 则 2 m  2 3  (4  2 m ) 4     m m  3 2 2    ··································································· 8 分 整理得 4 m  3 8 m  16 m 2  72 m  63 0  4 m  3 8 m  2 7 m  2 9 m  72 m  63 0  2 m m ( 2  8 m  7) 9(  m 2  8 m  7) 0  ( m  1)( m  7)( m 2  9) 0  1 1m  , 2 7m  , 2 m   (舍去) 9 y A O P B Q C x 故存在 1(1 3) P , , 2(7 3) P , 使 POQ△ 为等腰三角形.··············································10 分 注:以上各题的其它解法,请参照此标准记分.
分享到:
收藏