2022年2009年中考数学复习教材回归知识讲解 .pdf
![资源得分’ title=](/images/score_1.gif)
![资源得分’ title=](/images/score_1.gif)
![资源得分’ title=](/images/score_1.gif)
![资源得分’ title=](/images/score_1.gif)
![资源得分’ title=](/images/score_05.gif)
《2022年2009年中考数学复习教材回归知识讲解 .pdf》由会员分享,可在线阅读,更多相关《2022年2009年中考数学复习教材回归知识讲解 .pdf(33页珍藏版)》请在淘文阁 - 分享文档赚钱的网站上搜索。
1、2009 年中考数学复习教材回归知识讲解+例题解析+强化训练一次函数知识讲解1正比例函数的定义一般地,形如 y=kx(k 是常数,k0)的函数,叫做正比例函数,其中 k 叫做比例系数2正比例函数的图像正比例函数y=kx(k 是常数且k 0)的图像是一条经过原点(0,0)和点(1,k)?的直线,我们称它为直线y=kx;当 k0 时,直线 y=kx 经过第一,三象限,y 随着 x 的增大而增大,当k0 时,y 随 x 的增大而增大,此时若b0,则直线y=kx+b 经过第一,二,三象限;若b0,则直线 y=kx+b 经过第一,三,四象限,当k0 时,直线y=kx+b 经过第一,二,四象限;当b0)?
2、个单位得到一次函数 y=kx+b m;一次函数y=kx+b 沿着 x 轴向左(“”)、?右(“”)平移 n(n0)个单位得到一次函数y=k(xn)+b;一次函数沿着y 轴平移与沿着x 轴平移往往是同步进行的只不过是一种情况,两种表示罢了;直线y=kx+b 与 x 轴交点为(bk,0),与 y 轴交点为(0,b),且这两个交点与坐标原点构成的三角形面积为S=12bk b例题解析例 1(2006,江西省)已知直线L1经过点 A(1,0)与点 B(2,3),另一条直线L2经过点 B,且与 x 轴相交于点P(m,0)(1)求直线L1的解析式;(2)若 APB 的面积为3,求 m 的值【分析】函数图像上
3、的两点坐标也即是x,y 的两组对应值,?可用待定系数法求解,求函数与坐标轴所围成的三角形面积关键是求出函数解析式的k,b 的值【解答】(1)设直线L 的解析式为y=kx+b,由题意得0,23.kbkb解得1,1.kb所以,直线L1的解析式为y=x+1(2)当点 P 在点 A 的右侧时,AP=m(1)=m+1,有 SAPC=12(m+1)3=3解得 m=1,此时点P 的坐标为(1,0);当点 P 在点 A 的左侧时,AP=1m,有 S=(m1)3=3,解得 m=3,此时,点 P 的坐标为(3,0)综上所述,m 的值为 1 或 3【点评】先设一次函数的解析式,再代入点的坐标,利用方程组求解,其步骤
4、是:设、代,求、答例 2(2004,黑龙江省)下图表示甲,乙两名选手在一次自行车越野赛中,路程 y(km)随时间 x(min)的变化的图像(全程),根据图像回答下列问题:(1)求比赛开始多少分钟时,两人第一次相遇?(2)求这次比赛全程是多少千米?(3)求比赛开始多少分钟时,两人第二次相遇文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7
5、C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:
6、CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 H
7、Y4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 Z
8、N7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编
9、码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2
10、 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10 ZN7C8H4U6M3文档编码:CH1G2L5H5H2 HY4V2M9G4L10
11、 ZN7C8H4U6M3【分析】观察图像知,甲选手的路程y 随时间 x 变化是一个分段函数,第一次相遇时是在 AB 段,故求出15x 33 时的函数关系式;欲求出比赛全程,则需知乙的速度,这可由第一次相遇时的路程与时间的关系求得,要求第二次相遇时间,?即先求甲在BC 段的函数关系式,再求出BC 和 OD 的交点坐标即可【解答】(1)当 15x33 时,设 yAB=k1x+b1,将(15,5)与(33,7)代入得:1111515733kbkb解得1119103kbyAB=19x+103当 y=6 时,有:6=19x+103,解得 x=24比赛进行到24min 时,两人第一次相遇(2)设 yOD=
12、kx,将(24,6)代入得:6=24k,k=14yOD=14x 当 x=48 时,yOD=1448=12 比赛全程为12km(3)当 33x43 时,设 yBC=k2x+b2,将(33,7)和(43,12)代入得:22227331243kbkb文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E
13、2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y
14、3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S
15、1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J
16、10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8
17、V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1
18、R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码
19、:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1解得2212192kbyBC=12x1921192214xyxy解得19238xy比赛进行到38min 时,两人第二次相遇【点评】解答图像应用题的要领是从图像的形状特点、变化趋势、相关位置、相关数据出发,充分发掘图像所蕴含的信息,利用函数、方程(组)、不等式等知识去分析图像以解决问题例 3(2006,贵州铜仁)铜仁某水果销售公司准备从外地购买西瓜31t,柚子 12t,现计划租甲,乙两种货车共10 辆,将这批水果运到铜仁,已知甲种货车可装西瓜4t 和柚子 1t,乙种货车可装西瓜,柚子各2t(1)该公司安排甲,乙两种货车时
20、有几种方案?(2)若甲种货车每辆要付运输费1800 元,乙种货车每辆要付运输费1200 元,?则该公司选择哪种方案运费最少?最少运费是多少元?【解答】(1)设安排甲种货车x 辆,则安排乙种货车为(10 x)辆,依题意,得42(10)312(10)12xxxx解这个不等式组,得5.5x 8x 是整数,x 可取 6,7,8即安排甲,乙两种货车有三种方案:甲种货车6 辆,乙种货车4 辆甲种货车7 辆,乙种货车3 辆甲种货车8 辆,乙种货车2 辆(2)设运费为y 元,则 y=1800 x+1200(10 x)=600 x+12000 当 x 取 6 时,运费最少,最少运费是:15600 元【点评】本例
21、需要考生构建一元一次不等式和一次函数来解决实际问题,以考查学生运文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y
22、3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S
23、1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J
24、10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8
25、V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1R1文档编码:CL10E2G3S1Y3 HJ1S1F9L1J10 ZQ8V7Y5S1
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 2022年2009年中考数学复习教材回归知识讲解 2022 2009 年中 数学 复习 教材 回归 知识 讲解
![提示](https://www.taowenge.com/images/bang_tan.gif)
限制150内