2005年上海市初中毕业生统一学业考试数学试卷一、填空题(本大题共14题,满分42分) 1、 计算:()22x=2、 分解因式:22a a -= 3、计算:)11=4、函数y =的定义域是5、 如果函数()1f x x =+,那么()1f =6、 点A(2,4)在正比例函数的图象上,这个正比例函数的解析式是7、 如果将二次函数22y x =的图象沿y 轴向上平移1个单位,那么所得图象的函数解析式是8、 已知一元二次方程有一个根为1,那么这个方程可以是 (只需写出一个方程) 9、 如果关于x 的方程240x x a ++=有两个相等的实数根,那么a = 10、 一个梯形的两底长分别为6和8,这个梯形的中位线长为 11、 在△ABC 中,点D 、E 分别在边AB 和AC 上,且DE ∥BC ,如果AD =2,DB =4,AE =3,那么EC =12、 如图1,自动扶梯AB 段的长度为20米,倾斜角A为α,高度BC 为 米(结果用含α的三角比表示). 13、 如果半径分别为2和3的两个圆外切,那么这两个圆的圆心距是14、 在三角形纸片ABC 中,∠C =90°,∠A =30°,AC =3,折叠该纸片,使点A 与点B 重合,折痕与AB 、AC 分别相交于点D 和点E (如图2),折痕DE 的长为二、选择题:(本大题共4题,满分12分)15、 在下列实数中,是无理数的为 ( ) A 、0 B 、-3.5 CD16、 六个学生进行投篮比赛,投进的个数分别为2、3、3、5、10、13,这六个数的中位数为 ( )A 、3B 、4C 、5D 、617、 已知Rt △ABC 中,∠C =90°,AC =2,BC =3,那么下列各式中,正确的是( )图1图2A 、2sin 3B =B 、2cos 3B =C 、23tgB =D 、23ctgB = 18、 在下列命题中,真命题是 ( )A 、两个钝角三角形一定相似B 、两个等腰三角形一定相似C 、两个直角三角形一定相似D 、两个等边三角形一定相似 三、(本大题共3题,满分24分) 19、 (本题满分8分) 解不等式组:()315216x xx x +>-⎧⎨+-<⎩,并把解集在数轴上表示出来.20、 (本题满分8分) 解方程:228124x x x x x +-=+--x-5-4-3-2-15432O 121、 (本题满分8分,每小题满分各为4分)(1)在图3所示编号为①、②、③、④的四个三角形中,关于y 轴对称的两个三角形的编号为 ;关于坐标原点O 对称的两个三角形的编号为 ; (2)在图4中,画出与△ABC 关于x 轴对称的△A 1B 1C 1四、(本大题共4题,满分42分)22、 (本题满分10分,每小题满分各为5分)在直角坐标平面中,O 为坐标原点,二次函数2y x bx c =++的图象与x 轴的负半轴相交于点C (如图5),点C 的坐标为(0,-3),且BO =CO (1) 求这个二次函数的解析式; (2) 设这个二次函数的图象的顶点为M ,求AM 的长.23、(本题满分10分)已知:如图6,圆O是△ABC的外接圆,圆心O在这个三角形的高CD上,E、F分别是边AC和BC的中点,求证:四边形CEDF是菱形.24、 (本题满分10分,第(1)、(2)、(3)小题满分各为2分,第(4)小题满分4分) 小明家使用的是分时电表,按平时段(6:00-22:00)和谷时段(22:00-次日6:00)分别计费,平时段每度电价为0.61元,谷时段每度电价为0.30元,小明将家里2005年1月至5月的平时段和谷时段的用电量分别用折线图表示(如图7),同时将前4个月的用电量和相应电费制成表格(如表1) 根据上述信息,解答下列问题:(1) 计算5月份的用电量和相应电费,将所得结果填入表1中; (2) 小明家这5个月的月平均用电量为 度;(3) 小明家这5个月的月平均用电量呈 趋势(选择“上升”或“下降”);这5个月每月电费呈 趋势(选择“上升”或“下降”);(4) 小明预计7月份家中用电量很大,估计7月份用电量可达500度,相应电费将达243元,请你根据小明的估计,计算出7月份小明家平时段用电量和谷时段用电量.用电量(度)月份5月4月3月2月1月25、 (本题满分12分,每小题满分各为4分)在△ABC 中,∠ABC =90°,AB =4,BC =3,O 是边AC 上的一个动点,以点O 为圆心作半圆,与边AB 相切于点D ,交线段OC 于点E ,作EP ⊥ED ,交射线AB 于点P ,交射线CB 于点F 。
(1) 如图8,求证:△ADE ∽△AEP ;(2) 设OA =x ,AP =y ,求y 关于x 的函数解析式,并写出它的定义域; (3) 当BF =1时,求线段AP 的长.图9(备用图)图8BCC2005年上海市初中毕业生统一学业考试数学试卷参考答案()4221.;2.(2);3.1;4.0;5.2;6.()2;7.()21;8.0;9.4;10.7;11.6;12.20sin ;13.5;14.1;15.16.17.18..315119.2162:144,1;222-6,414x a a x f x x f x x x x C B C D x x x x x x x x x x α-≥==+-=+>-⎧⎨+-<⎩>>+<<∴<<一.填空二.选择三解答()()解由()得由()得原不等式组的解集为23322222820.124(1)(2)(2)(2)(2)(2)(1)(2)8(1)44444889161209161200,x x x x x x x x x x x x x x x x x x x x x x x x x x x +-=+--++-+--+++=+-------=+---=++=∆<∴解:两边同乘以,整理得:原方程无解21.(1):(1),(2);(1),(3)(2)如图:222.1(0,3),|3|3,3,3,(3,0)9330,630,2()232(2)122(1)1234,(1,0)(1,4)C OC c OC BO BO B b b b f x x x b a f A M AM -=-=∴=-=∴=∴+-=+==-∴=----=-==--=---∴==解:()又23.1122AB CD AB CD AD BD CD CD CAD CBD A B AC BC E F AC BC D AB DF CE AE DE CF BC DE DF CE CF CEDF ⊥∴==∴∆≅∆∴∠=∠⇒=∴====∴===∴证明:为弦,为直径所在的直线且又又,分别为,的中点,为中点,,四边形为菱形24、1110,53.15(2)99(3)4500-)0.610.3(500-)2430.611500.32430.3193300,500-200300200x x x x x x x x x +=++-====解:()上升,上升()设平时段度,谷时用(度答:平时段度,谷时用度25.1909090AP D ODA PED OD OE ODE OEDODE OED EDA PEA A A ADE AEP∴∠=∠=︒=∴∠=∠∴︒+∠=︒+∠∴∠=∠∠=∠∴∆∆()证明:连结OD切半圆于,又,,又22334,555846416584525555(0)OD CB OA AC OD OD x OE AD x x ADE AEP xAP AE y xy x y xAE AD x x x ==⇒===∆∆∴=⇒=⇒=⇒=>()同理可得:(3)5(46,90512661255E C x AP AB DO BE H DHE DJEHD x PBE PDH PFB PHD PB PB AP x x >>∆≅∆∴=∠=∠=︒∴∆∆∴=⇒=⇒=由题意可知存在三种情况但当在点左侧时BF显然大于4所以不合舍去当时如图)延长,交于易证54,1261255422x P B DO PE H DHE EJD PBF PDHBP BP x x AP <∆≅∆∆∆∴=⇒=∴=-=当时点在点的右侧延长交于点同理可得J2006年上海市初中毕业生统一学业考试数学试卷(满分150分,考试时间100分钟)题号一二三 四总分17 18 19 20 21 22 23 24 25 得分考生注意:1.本卷含四大题,共25题;2.除第一、二大题外,其余各题如无特别说明,都必须写出证明或计算的主要步骤. 一.填空题:(本大题共12题,满分36分)【只要求直接写出结果,每个空格填对得3分,否则得零分】 1=__________.2.计算:12x x+=__________.3.不等式60x ->的解集是__________.4.分解因式:2x xy +=__________. 5.函数13y x =-的定义域是__________. 61=的根是__________.7.方程2340x x +-=的两个实数根为1x ,2x ,则12x x =__________.8.用换元法解方程2221221x x x x -+=-时,如果设221x y x =-,那么原方程可化为__________.9.某型号汽油的数量与相应金额的关系如图1所示,那么这种汽油的单价是每升__________元.10.已知在ABC △和111A B C △中,11AB A B =,1A A =∠∠,要使111ABC A B C △≌△,还需添加一个条件,这个条件可以是__________.11.已知圆O 的半径为1,点P 到圆心O 的距离为2,过点P 引圆O 的切线,那么切线长是__________.12.在中国的园林建筑中,很多建筑图形具有对称性.图2是一个破损花窗的图形,请把它补画成中心对称图形.数量(单位:升) 图1二.选择题:(本大题共4题,满分16分)【下列各题的四个结论中,有且只有一个结论是正确的,把正确结论的代号写在题后的圆括号内,选对得4分;不选、错选或者多选得零分】 13.在下列方程中,有实数根的是( ) A.2310x x ++=1=- C.2230x x ++=D.111x x x =-- 14.二次函数()213y x =--+图象的顶点坐标是( ) A.()13-,B.()13,C.()13--,D.()13-,15.在ABC △中,AD 是BC 边上的中线,G 是重心.如果6AG =,那么线段DG 的长为( ) A.2 B.3 C.6 D.12 16.在下列命题中,真命题是( ) A.两条对角线相等的四边形是矩形 B.两条对角线互相垂直的四边形是菱形C.两条对角线互相平分的四边形是平行四边形 D.两条对角线互相垂直且相等的四边形是正方形 三.(本大题共5题,满分48分) 17.(本题满分9分)先化简,再求值:2111x x x -⎛⎫+÷ ⎪⎝⎭,其中x =18.(本题满分9分) 解方程组:23010x y x y --=⎧⎨++=⎩,.19.(本题满分10分,每小题满分各5分)已知:如图3,在ABC △中,AD 是边BC 上的高,E 为边AC 的中点,14BC =,12AD =,4sin 5B =.求(1)线段DC 的长;(2)tg EDC ∠的值.20.(本题满分10分,第(1)小题满分3分,第(2)小题满分4分,第(3)小题满分3分)某市在中心城区范围内,选取重点示范路口进行交通文明状况满意度调查,将调查结果的满意度分为:不满意、一般、较满意、满意和非常满意,依次以红、橙、黄、蓝、绿五色标识.今年五月发布的调查结果中,橙色与黄色标识路口数之和占被调查路口总数的15%.结合未画完整的图4中所示信息,回答下列问题: (1)此次被调查的路口总数是__________;(2)将图4中绿色标识部分补画完整,并标上相应的路口数;(3)此次被调查路口的满意度能否作为该市所有路口交通文明状况满意度的一个随机样本?答:____________________.21.(本题满分10分)本市新建的滴水湖是圆形人工湖.为测量该湖的半径,小杰和小丽沿湖边选取A ,B ,C 三根木柱,使得A ,B 之间的距离与A ,C 之间的距离相等,并测得BC 长为240米,A 到BC 的距离为5米,如图5所示.请你帮他们求出滴水湖的半径.AE CD B 图3红橙黄 蓝绿标识图4图5四.(本大题共4题,满分50分) 22.(本题满分12分,第(1)小题满分5分,第(2)小题满分7分)如图6,在直角坐标系中,O 为原点.点A 在第一象限,它的纵坐标是横坐标的3倍,反比例函数12y x=的图象经过点A . (1)求点A 的坐标;(2)如果经过点A 的一次函数图象与y 轴的正半轴交于点B ,且OB AB =,求这个一次函数的解析式. 23.(本题满分12分,每小题满分各6分)已知:如图7,在梯形ABCD 中,AD BC ∥,AB DC =.点E ,F ,G 分别在边AB ,BC ,CD 上,AE GF GC ==.(1)求证:四边形AEFG 是平行四边形;(2)当2FGC EFB =∠∠时,求证:四边形AEFG 是矩形.24.(本题满分12分,第(1)小题满分5分,第(2)小题满分3分,第(3)小题满分4分)如图8,在直角坐标系中,O 为原点.点A 在x 轴的正半轴上,点B 在y 轴的正半轴上,tg 2OAB =∠.二次函数22y x mx =++的图象经过点A ,B ,顶点为D .(1)求这个二次函数的解析式;图6 B E A D G图7 F△绕点A顺时针旋转90后,点B落到点C的位置.将上述二次函数图象沿(2)将OABy 轴向上或向下平移后经过点C .请直接写出点C 的坐标和平移后所得图象的函数解析式; (3)设(2)中平移后所得二次函数图象与y 轴的交点为1B ,顶点为1D .点P 在平移后的二次函数图象上,且满足1PBB △的面积是1PDD △面积的2倍,求点P 的坐标.25.(本题满分14分,第(1)小题满分4分,第(2)小题满分7分,第(3)小题满分3分)已知点P 在线段AB 上,点O 在线段AB 延长线上.以点O 为圆心,OP 为半径作圆,点C 是圆O 上的一点.(1)如图9,如果2AP PB =,PB BO =.求证:CAO BCO △∽△; (2)如果AP m =(m 是常数,且1m >),1BP =,OP 是OA ,OB 的比例中项.当点C 在圆O 上运动时,求:AC BC 的值(结果用含m 的式子表示); (3)在(2)的条件下,讨论以BC 为半径的圆B 和以CA 为半径的圆C 的位置关系,并写出相应m 的取值范围.2006年上海市初中毕业生统一学业考试CA PB O 图9数学试卷答案要点与评分标准说明:1.解答只列出试题的一种或几种解法.如果考生的解法与所列解法不同,可参照解答中评分标准相应评分.2.第一大题只要求直接写出结果,每个空格填对得3分,否则得零分;第二大题每题选对得4分,不选、错选或者多选得零分;17题至25题中右端所注的分数,表示考生正确做对这一步应得分数.评分时,给分或扣分均以1分为单位. 答案要点与评分标准 一.填空题:(本大题共12题,满分36分) 1.2; 2.3x; 3.6x >;4.()x x y +;5.3x ≠;6.1;7.4-; 8.2210y y -+=(或12y y+=);9.5.09;10.1B B =∠∠(或1C C =∠∠,或11AC A C =); 1112.答案见图1.二.选择题:(本大题共4题,满分16分) 13.A; 14.B; 15.B;16.C.三.(本大题共5题,满分48分)17.解:原式211x x x x+-=÷ ····································································· (2分) ()()111x x x x x +-+=÷ ·························································· (2分) ()()111x xx x x +=+- ···························································· (1分)11x =-, ············································································ (2分)当x =1==. ············································· (2分)图118.解:消去y 得220x x +-=, ····························································· (3分) 得12x =-,21x =, ··································································· (3分) 由12x =-,得15y =-, ······························································ (1分) 由21x =,得22y =-, ······························································· (1分) ∴原方程组的解是1125x y =-⎧⎨=-⎩,;2212x y =⎧⎨=-⎩,.············································ (1分) 19.解:(1)在Rt BDA △中,90BDA =∠,12AD =,4sin 5AD B AB ==, ··· (1分) 15AB ∴=. ················································································· (1分)9BD ∴==. ·········································· (2分) 1495DC BC BD ∴=-=-=. ······················································ (1分) (2)[方法一]过点E 作EF DC ⊥,垂足为F ,EF AD ∴∥. ··········· (1分) AE EC =,1522DF DC ∴==,162EF AD ==. ························· (2分) ∴在Rt EFD △中,90EFD =∠,12tg 5EF EDC DF ==∠. ················· (2分) [方法二]在Rt ADC △中,90ADC =∠,12tg 5AD C DC ==. ············ (2分) DE 是斜边AC 上的中线,12DE AC EC ∴==. ····························· (1分)EDC C ∴=∠∠. ········································································· (1分)12tg tg 5EDC C ∴==∠. ······························································· (1分) 20.(1)60; ························································································ (3分) (2)图略(条形图正确,得2分;标出数字10,得2分); ························ (4分) (3)不能.······················································································· (3分) 21.解:设圆心为点O ,连结OB ,OA ,OA 交线段BC 于点D . ·················· (1分)AB AC =,AB AC ∴=.OA BC ∴⊥,且11202BD DC BC ===. ································································································ (1分) 由题意,5DA =. ······································································ (1分) 在Rt BDO △中,222OB OD BD =+, ··········································· (2分) 设OB x =米, ············································································ (1分) 则()2225120x x =-+, ······························································ (2分)1442.5x ∴=. ·········································································· (1分) 答:滴水湖的半径为1442.5米. ···················································· (1分) 四.(本大题共4题,满分50分) 22.解:(1)由题意,设点A 的坐标为()3a a ,,0a >. ································ (1分)点A 在反比例函数12y x =的图象上,得123a a=, ···························· (1分) 解得12a =,22a =-, ·································································· (1分) 经检验12a =,22a =-是原方程的根,但22a =-不符合题意,舍去. ···· (1分) ∴点A 的坐标为()26,. ·································································· (1分)(2)由题意,设点B 的坐标为()0m ,. ··········································· (1分)0m >,m ∴=··················································· (2分)解得103m =,经检验103m =是原方程的根,∴点B 的坐标为1003⎛⎫⎪⎝⎭,. ·· (1分)设一次函数的解析式为103y kx =+, ················································· (1分) 由于这个一次函数图象过点()26A ,,10623k ∴=+,得43k =. ············ (1分) ∴所求一次函数的解析式为41033y x =+. ·········································· (1分)23.证明:(1)在梯形ABCD 中,AB DC =,B C ∴=∠∠. ···················· (2分) GF GC =,C GFC ∴=∠∠. ····················································· (1分) B GFC ∴=∠∠,AB GF ∴∥,即AE GF ∥. ································ (1分) AE GF =,∴四边形AEFG 是平行四边形. ··································· (2分) (2)过点G 作GH FC ⊥,垂足为H . ············································ (1分)GF GC =,12FGH FGC ∴=∠∠. ············································· (1分) 2FGC EFB =∠∠,FGH EFB ∴=∠∠.····································· (1分)90FGH GFH +=∠∠,90EFB GFH ∴+=∠∠. ······················ (1分)90EFG ∴=∠. ·········································································· (1分)四边形AEFG 是平行四边形,∴四边形AEFG 是矩形. ···················· (1分)24.解:(1)由题意,点B 的坐标为()02,, ················································ (1分)2OB ∴=,tg 2OAB =∠,即2OBOA=. 1OA ∴=.∴点A 的坐标为()10,. ··················································· (2分) 又二次函数22y x mx =++的图象过点A ,2012m ∴=++.解得3m =-, ··············································································· (1分) ∴所求二次函数的解析式为232y x x =-+. ······································ (1分) (2)由题意,可得点C 的坐标为()31,, ············································ (2分) 所求二次函数解析式为231y x x =-+. ············································· (1分) (3)由(2),经过平移后所得图象是原二次函数图象向下平移1个单位后所得的图象,那么对称轴直线32x =不变,且111BB DD ==. ····································· (1分)点P 在平移后所得二次函数图象上,设点P 的坐标为()231x x x -+,.在1PBB △和1PDD △中,112PBB PDD S S =△△,∴边1BB 上的高是边1DD 上的高的2倍.①当点P 在对称轴的右侧时,322x x ⎛⎫=-⎪⎝⎭,得3x =,∴点P 的坐标为()31,; ②当点P 在对称轴的左侧,同时在y 轴的右侧时,322x x ⎛⎫=- ⎪⎝⎭,得1x =, ∴点P 的坐标为()11-,;③当点P 在y 轴的左侧时,0x <,又322x x ⎛⎫-=-⎪⎝⎭,得30x =>(舍去), ∴所求点P 的坐标为()31,或()11-,. ················································ (3分) 25.(1)证明:2AP PB PB BO PO ==+=,2AO PO ∴=.2AO POPO BO∴==. ········································································ (2分) PO CO =, ··············································································· (1分) AO COCO BO∴=.COA BOC =∠∠,CAO BCO ∴△∽△.················· (1分) (2)解:设OP x =,则1OB x =-,OA x m =+,OP 是OA ,OB 的比例中项, ()()21x x x m ∴=-+, ·································································· (1分) 得1m x m =-,即1mOP m =-. ························································· (1分) 11OB m ∴=-. ············································································· (1分) OP 是OA ,OB 的比例中项,即OA OPOP OB=, OP OC =,OA OCOC OB∴=. ·························································· (1分) 设圆O 与线段AB 的延长线相交于点Q ,当点C 与点P ,点Q 不重合时, AOC COB =∠∠,CAO BCO ∴△∽△. ······································ (1分) AC OCBC OB∴=. ············································································· (1分) AC OC OP m BC OB OB ∴===;当点C 与点P 或点Q 重合时,可得AC m BC =, ∴当点C 在圆O 上运动时,:AC BC m =; ········································ (1分) (3)解:由(2)得,AC BC >,且()()11AC BC m BC m -=->,()1AC BC m BC +=+,圆B 和圆C 的圆心距d BC =,显然()1BC m BC <+,∴圆B 和圆C 的位置关系只可能相交、内切或内含. 当圆B 与圆C 相交时,()()11m BC BC m BC -<<+,得02m <<,1m >,12m ∴<<; ·································································· (1分)。