2012版数学一轮精品复习学案：2.1函数及其表示

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stressed that promoting the comprehensive revitalization should focus on economic construction as the central focus with, pay special attention to grasp the implementation of five development concepts, deepening reform and promoting the all-round opening up, ensuring and improving people's livelihood, strengthen the construction of ecological civilization, \opment mix. To with new development concept measure work, and command action, and training cadres, in implement implementation new development concept in the looking for opportunities, and build highlights, and expand advantage; to full deepening reform, break bound the aspects created vitality of system mechanism obstacles; to active advance full aspects opening, participation \cast Russian Economic Corridor%uarantees and improved livelihood, strongly won poverty battle; to strengthening ecological civilization construction, for sustainable development reserved space, for future generations left sky blue, and to green, and water clear of better homes. We must in-depth implement implementation new development concept, insisted to economic construction for Center, firmly caught development this first priority, absorbed make construction, heart no distractions caught development, speed up development \ndustry\, in-depth implementation \e big engineering\big environment\out of a article quality more high, and benefits better, and structure more excellent of transformation development of road. To strengthen ecological construction. On March 22, the deep restructuring examined and adopted the opinion on perfecting compensation mechanism of ecological protection, proposed to explore the establishment of diversified ecological compensation mechanism, progressive realization of forests, grasslands, wetlands and other areas of focus and key ecological function and other important regional ecological compensation coverage, the ecological advantages of the region will be further highlighted. We need to go green eco-building, as the essential policy, in strict accordance with the State of main function region construction requirements, careful implementation and Xiaoxing ' an mountains forest ecological protection and economirestructuring plan for the construction of sky blue, ... Acts prohibited by picking up the remaining wells in standing timber. To focus on forest resource conservation, increase the acquisition and supervision of cold storage, no buy fruit, encourage support to leading enterprises, workers ' cooperatives as a unit, the contract management of forest resources, the rational protection and utilization of resources. To work actively towards policy aimed from the level of the State Forestry Administration formulated regulations to protect forest resources as soon as possible to achieve law and regulation to protect forest resources. Should focus on forest fire prevention. Fire safety is the first priority2012版高三数学一轮精品复习学案：函数、导数及其应用

【知识特点】

1．函数、导数及其应用是高中数学的重要内容，本章主要包括函数的概念及其性质，基本初等函数Ⅰ（指数函数、对数函数、幂函数），导数的概念，导数及其几何意义，导数与函数的单调性、最值，导数在实际问题中的应用等内容。

2．本章内容集中体现了函数与方程、数形结合、分类讨论的思想方法，函数的类型较多，概念、公式较多，具有较强的综合性。

【重点关注】

1．函数的概念及其性质（单调性、奇偶性、周期性、对称性）是高考考查的主要内容，函数的定义域、解析式、值域是高考考查重点，函数性质的综合考查在历年考试中久考不衰，应重点研究。

2．函数的图象及其变换既是高考考查的重点，又是学生学习的一个难点，应注意区分各函数的图象及图象的变换，利用图象来研究性质。

3．导数的几何意义，导数在函数的最值及单调性方面的应用是高中数学的一个重点内容，也是高等数学的必修内容，是近几年高考的一大热点，复习时应引起足够的重视。

4．注意思想方法的应用。数形结合思想、函数与方程的思想、分类讨论思想在各种题型中均有体现，应引起重视。

【地位与作用】

一、函数在高考中的地位与作用

从2009年、2010年和2011年的全国各地的高考试题中可以看出，近几年高考在函数中的考查有如下特点：

1、知识点的考查情况

①映射与函数：以考查概念与运算为主，部分涉及新定义运算；

②定义域、值域、解析式是考查的重点，而且比较稳定，有时结合其它知识点（一本部分内容为背景），分段函数较多、花样翻新；

③函数的单调性在历年考试中久考不衰，且比例有上升趋势，和导函数联系较多； ④函数的奇偶性主要和单调性、不等式、最值、三角函数等综合，与周期性、对称性、抽象函数等问题联系较多；

⑤反函数出现在选择题、填空题中，考反函数概念运算可能性较大，若出现在解答题中，则必定与单调性、奇偶性、不等式、导函数等知识综合，难度较大；

he first responsibility of the forest, 26th spring area has fully deployed to the fire, has now entered the fire, we have to be on duty, and defend. Determined to overcome paralysis, must not \past, the reduced requirements during the period. To apply strictly the party with the responsibility, must shoulder the responsibility of the Party Secretary in particular, really practice pipes, it can never shuaishouzhanggui, be sure to layer the implementation falls fire responsibility, to ensure that no major forest fires. To adhere to balanced, correctly handle the relationship between fire and project construction, industrial development, to \cond, to speed up the development of six major industries. Promote development in our region, the key is to give full play to resource advantage to build eco-oriented \new engine of economic growth. Firm confidence. Practice has proved that the \central and provincial requirements, and meet the actual da hinggan mountains, through active efforts have been showing a strong momentum of development. So, in the \development, we must be firm in faith, go all out, perseverance, one caught in the end, convinced that Castle is not relaxed, does not reach the target will never give up. Should focus on industrial projects. Project is to accelerate the industrial development of important support and backing. Industrial project construction, my area there are few in number, small size, low level problems. This year, the project as his party has \st project\have to work hard to project construction. Especially effective during short, catching project shall not, slow, dragging not allowed. All localities should conscientiously implement the project leadership system, timetable, roadmap, and coordinate services, tracking the whole process forward, inverted durations, speeding up progress and seek practical results. Poised to break the project build Set challenges, to accelerate the pace of preliminary formalities, the enterprises have difficulties to pull one way and also help in a timely manner to help businesses market, enhance confidence, urging work as soon as possible. To strengthen the project analysis, proper risk analysis and improve project success rates. (Specific to the XX, we still want to make good use of agricultural advantages, relying on the upper reaches of the forest in the fresh air and XXX pure water and other resources, create high-quality, high-grade green food brands, truly reflect the original character. Meanwhile, adhere to the project as the breakthrough to promote economic development around the \chain\on to forming projects, dig potential projects, focus on key projects, actively cultivating the new leading industries and new sources of economic growth). To promote investment. More accurate professional business, and based my industrial base and resources, aimed at national industrial layoutstressed that promoting the comprehensive revitalization should focus on economic construction as the central focus with, pay special attention to grasp the implementation of five development concepts, deepening reform and promoting the all-round opening up, ensuring and improving people's livelihood, strengthen the construction of ecological civilization, \opment mix. To with new development concept measure work, and command action, and training cadres, in implement implementation new development concept in the looking for opportunities, and build highlights, and expand advantage; to full deepening reform, break bound the aspects created vitality of system mechanism obstacles; to active advance full aspects opening, participation \cast Russian Economic Corridor%uarantees and improved livelihood, strongly won poverty battle; to strengthening ecological civilization construction, for sustainable development reserved space, for future generations left sky blue, and to green, and water clear of better homes. We must in-depth implement implementation new development concept, insisted to economic construction for Center, firmly caught development this first priority, absorbed make construction, heart no distractions caught development, speed up development \ndustry\pth implementation \e big engineering\big environment\out of a article quality more high, and benefits better, and structure more excellent of transformation development of road. To strengthen ecological construction. On March 22, the deep restructuring examined and adopted the opinion on perfecting compensation mechanism of ecological protection, proposed to explore the establishment of diversified ecological compensation mechanism, progressive realization of forests, grasslands, wetlands and other areas of focus and key ecological function and other important regional ecological compensation coverage, the ecological advantages of the region will be further highlighted. We need to go green eco-building, as the essential policy, in strict accordance with the State of main function region construction requirements, careful implementation and Xiaoxing ' an mountains forest ecological protection and economirestructuring plan for the construction of sky blue, ... Acts prohibited by picking up the remaining wells in standing timber. To focus on forest resource conservation, increase the acquisition and supervision of cold storage, no buy fruit, encourage support to leading enterprises, workers ' cooperatives as a unit, the contract management of forest resources, the rational protection and utilization of resources. To work actively towards policy aimed from the level of the State Forestry Administration formulated regulations to protect forest resources as soon as possible to achieve law and regulation to protect forest resources. Should focus on forest fire prevention. Fire safety is the first priority ⑥二次函数问题是每年的必考题，一方面直接考查二次函数，另一方面是利用二次函数的性质解题，三个“二次”问题（即二次函数、二次方程、二次不等式）是函数考试题中永恒的主题

⑦指数函数与对数函数以基本概念、性质为主设计试题，考查指数、对数的定义域、值域、单调性和运算，选择、填空题属中等难度，若解答题涉及到指、对数函数，往往难度会上升；

⑧函数的图像与最值每年必考，体现“形是数的直观反映，数是形的抽象概括”，是数学思想方法中的数相结合思想的最直接的表现形式，尤其是函数y=x+a/x（a＞0）的图像和性质，从未间断过；

⑨函数应用题与综合应用题是最能体现考生函数水平的试题：一次函数、二次函数、y=x+a/x（a＞0）型、指数型、对数型与现实生活相结合，考查学生的建模能力，而函数与数列、不等式、导函数等众多知识的交汇已经成为函数综合应用中的典型问题。

2、常考题型及分值情况

函数在选择、填空、解答三种题型中每年都有考题，所占分值30分以上，占全卷的20%以上。在高考中占有重要地位。

3、命题热点及生长点情况

近年来有关函数内容的高考命题趋势是：

①全方位. 近几年来的高考题中，函数的所有知识点都考过，虽然近几年不强调知识点的覆盖率，但每一年函数知识点的覆盖率依然没有减少。

②多层次. 在每年的高考题中，函数题抵挡、中档、高档难度都有，且选择、填空、解答题题型齐全。抵挡难度一般仅涉及函数本身的内容，诸如定义域、值域、单调性、周期性、图像、反函数，且对能力的要求不高；中、高档难度题多为综合程度较大的问题，或者是函数与其它知识结合，或者是多种方法的渗透。

③巧综合. 为了突出函数在中学中的主要地位，近几年来高考强化了函数对其它知识的渗透，加大了以函数为载体的多种方法、多种能力的综合程度。

④变角度. 出于“立意”和创新情况的需要，函数试题设置问题的角度和方式也不断创新。重视函数思想的考查，加大了函数应用题、探索题和信息题的考查力度，从而使函数考题显得新颖、生动、灵活。

二、导数在高考中的地位与作用

导数是高中数学中重要的内容，是解决实际问题的强有力的数学工具，运用导数的有关知识，研究函数的性质：单调性、极值和最值是高考的热点问题。在高考中考察形式多种多样，以选择题、填空题等主观题目的形式考察基本概念、运算及导数的应用，也经常以解答题形式和其它数学知识结合起来，综合考察利用导数研究函数的单调性、极值、最值，估计2010年高考继续以

he first responsibility of the forest, 26th spring area has fully deployed to the fire, has now entered the fire, we have to be on duty, and defend. Determined to overcome paralysis, must not \past, the reduced requirements during the period. To apply strictly the party with the responsibility, must shoulder the responsibility of the Party Secretary in particular, really practice pipes, it can never shuaishouzhanggui, be sure to layer the implementation falls fire responsibility, to ensure that no major forest fires. To adhere to balanced, correctly handle the relationship between fire and project construction, industrial development, to \cond, to speed up the development of six major industries. Promote development in our region, the key is to give full play to resource advantage to build eco-oriented \new engine of economic growth. Firm confidence. Practice has proved that the \central and provincial requirements, and meet the actual da hinggan mountains, through active efforts have been showing a strong momentum of development. So, in the \development, we must be firm in faith, go all out, perseverance, one caught in the end, convinced that Castle is not relaxed, does not reach the target will never give up. Should focus on industrial projects. Project is to accelerate the industrial development of important support and backing. Industrial project construction, my area there are few in number, small size, low level problems. This year, the project as his party has \have to work hard to project construction. Especially effective during short, catching project shall not, slow, dragging not allowed. All localities should conscientiously implement the project leadership system, timetable, roadmap, and coordinate services, tracking the whole process forward, inverted durations, speeding up progress and seek practical results. Poised to break the project build Set challenges, to accelerate the pace of preliminary formalities, the enterprises have difficulties to pull one way and also help in a timely manner to help businesses market, enhance confidence, urging work as soon as possible. To strengthen the project analysis, proper risk analysis and improve project success rates. (Specific to the XX, we still want to make good use of agricultural advantages, relying on the upper reaches of the forest in the fresh air and XXX pure water and other resources, create high-quality, high-grade green food brands, truly reflect the original character. Meanwhile, adhere to the project as the breakthrough to promote economic development around the \chain\on to forming projects, dig potential projects, focus on key projects, actively cultivating the new leading industries and new sources of economic growth). To promote investment. More accurate professional business, and based my industrial base and resources, aimed at national industrial layoutstressed that promoting the comprehensive revitalization should focus on economic construction as the central focus with, pay special attention to grasp the implementation of five development concepts, deepening reform and promoting the all-round opening up, ensuring and improving people's livelihood, strengthen the construction of ecological civilization, \opment mix. To with new development concept measure work, and command action, and training cadres, in implement implementation new development concept in the looking for opportunities, and build highlights, and expand advantage; to full deepening reform, break bound the aspects created vitality of system mechanism obstacles; to active advance full aspects opening, participation \cast Russian Economic Corridor%uarantees and improved livelihood, strongly won poverty battle; to strengthening ecological civilization construction, for sustainable development reserved space, for future generations left sky blue, and to green, and water clear of better homes. We must in-depth implement implementation new development concept, insisted to economic construction for Center, firmly caught development this first priority, absorbed make construction, heart no distractions caught development, speed up development \ndustry\pth implementation \e big engineering\big environment\out of a article quality more high, and benefits better, and structure more excellent of transformation development of road. To strengthen ecological construction. On March 22, the deep restructuring examined and adopted the opinion on perfecting compensation mechanism of ecological protection, proposed to explore the establishment of diversified ecological compensation mechanism, progressive realization of forests, grasslands, wetlands and other areas of focus and key ecological function and other important regional ecological compensation coverage, the ecological advantages of the region will be further highlighted. We need to go green eco-building, as the essential policy, in strict accordance with the State of main function region construction requirements, careful implementation and Xiaoxing ' an mountains forest ecological protection and economirestructuring plan for the construction of sky blue, ... Acts prohibited by picking up the remaining wells in standing timber. To focus on forest resource conservation, increase the acquisition and supervision of cold storage, no buy fruit, encourage support to leading enterprises, workers ' cooperatives as a unit, the contract management of forest resources, the rational protection and utilization of resources. To work actively towards policy aimed from the level of the State Forestry Administration formulated regulations to protect forest resources as soon as possible to achieve law and regulation to protect forest resources. Should focus on forest fire prevention. Fire safety is the first priority上面的几种形式考察不会有大的变化：

（1）考查形式为：选择题、填空题、解答题各种题型都会考察，选择题、填空题一般难度不大，属于高考题中的中低档题，解答题有一定难度，一般与函数及解析几何结合，属于高考的中低档题；

（2）2010年高考可能涉及导数综合题，以导数为数学工具考察：导数的物理意义及几何意义，复合函数、数列、不等式等知识。

定积分是新课标教材新增的内容，主要包括定积分的概念、微积分基本定理、定积分的简单应用，由于定积分在实际问题中非常广泛，因而07年的高考预测会在这方面考察，预测2010年高考呈现以下几个特点：

（1）注意基本概念、基本性质、基本公式的考察及简单的应用；高考中本讲的题目一般为选择题、填空题，考查定积分的基本概念及简单运算，属于中低档题；

（2）定积分的应用主要是计算面积，诸如计算曲边梯形的面积、变速直线运动等实际问题要很好的转化为数学模型

第一节、函数及其表示

【高考目标导航】

一、考纲点击

1．了解构成函数的要素，会求一些简单函数的定义域和值域；了解映射的概念。 2．在实际情境中，会根据不同的需要选择恰当的方法（如图象法、列表法、解析法）表示函数。

3．了解简单的分段函数，并能简单应用。二、热点、难点提示

1．函数的概念、表示方法、分段函数是近几年高考的热点； 2．函数的概念、三要素、分段函数等问题是重点，也是难点；

3．题型以选择题和填空题为主，与其他知识点交汇则以解答题的形式出现。

【考纲知识梳理】

一、函数与映射的概念两集合函数设A、B是两个非空数集映射设A、B是两个非空集合 he first responsibility of the forest, 26th spring area has fully deployed to the fire, has now entered the fire, we have to be on duty, and defend. Determined to overcome paralysis, must not \past, the reduced requirements during the period. To apply strictly the party with the responsibility, must shoulder the responsibility of the Party Secretary in particular, really practice pipes, it can never shuaishouzhanggui, be sure to layer the implementation falls fire responsibility, to ensure that no major forest fires. To adhere to balanced, correctly handle the relationship between fire and project construction, industrial development, to \cond, to speed up the development of six major industries. Promote development in our region, the key is to give full play to resource advantage to build eco-oriented \new engine of economic growth. Firm confidence. Practice has proved that the \central and provincial requirements, and meet the actual da hinggan mountains, through active efforts have been showing a strong momentum of development. So, in the \development, we must be firm in faith, go all out, perseverance, one caught in the end, convinced that Castle is not relaxed, does not reach the target will never give up. Should focus on industrial projects. Project is to accelerate the industrial development of important support and backing. Industrial project construction, my area there are few in number, small size, low level problems. This year, the project as his party has \have to work hard to project construction. Especially effective during short, catching project shall not, slow, dragging not allowed. All localities should conscientiously implement the project leadership system, timetable, roadmap, and coordinate services, tracking the whole process forward, inverted durations, speeding up progress and seek practical results. Poised to break the project build Set challenges, to accelerate the pace of preliminary formalities, the enterprises have difficulties to pull one way and also help in a timely manner to help businesses market, enhance confidence, urging work as soon as possible. To strengthen the project analysis, proper risk analysis and improve project success rates. (Specific to the XX, we still want to make good use of agricultural advantages, relying on the upper reaches of the forest in the fresh air and XXX pure water and other resources, create high-quality, high-grade green food brands, truly reflect the original character. Meanwhile, adhere to the project as the breakthrough to promote economic development around the \chain\on to forming projects, dig potential projects, focus on key projects, actively cultivating the new leading industries and new sources of economic growth). To promote investment. More accurate professional business, and based my industrial base and resources, aimed at national industrial layoutstressed that promoting the comprehensive revitalization should focus on economic construction as the central focus with, pay special attention to grasp the implementation of five development concepts, deepening reform and promoting the all-round opening up, ensuring and improving people's livelihood, strengthen the construction of ecological civilization, \opment mix. To with new development concept measure work, and command action, and training cadres, in implement implementation new development concept in the looking for opportunities, and build highlights, and expand advantage; to full deepening reform, break bound the aspects created vitality of system mechanism obstacles; to active advance full aspects opening, participation \cast Russian Economic Corridor%uarantees and improved livelihood, strongly won poverty battle; to strengthening ecological civilization construction, for sustainable development reserved space, for future generations left sky blue, and to green, and water clear of better homes. We must in-depth implement implementation new development concept, insisted to economic construction for Center, firmly caught development this first priority, absorbed make construction, heart no distractions caught development, speed up development \ndustry\pth implementation \e big engineering\big environment\out of a article quality more high, and benefits better, and structure more excellent of transformation development of road. To strengthen ecological construction. On March 22, the deep restructuring examined and adopted the opinion on perfecting compensation mechanism of ecological protection, proposed to explore the establishment of diversified ecological compensation mechanism, progressive realization of forests, grasslands, wetlands and other areas of focus and key ecological function and other important regional ecological compensation coverage, the ecological advantages of the region will be further highlighted. We need to go green eco-building, as the essential policy, in strict accordance with the State of main function region construction requirements, careful implementation and Xiaoxing ' an mountains forest ecological protection and economirestructuring plan for the construction of sky blue, ... Acts prohibited by picking up the remaining wells in standing timber. To focus on forest resource conservation, increase the acquisition and supervision of cold storage, no buy fruit, encourage support to leading enterprises, workers ' cooperatives as a unit, the contract management of forest resources, the rational protection and utilization of resources. To work actively towards policy aimed from the level of the State Forestry Administration formulated regulations to protect forest resources as soon as possible to achieve law and regulation to protect forest resources. Should focus on forest fire prevention. Fire safety is the first priority 对应关系如果按照某种确定的对应关系如果按某一个确定的对应关系f:A?B f，使对于集合A中的任意一个数x，在集合B中都有唯一确定的数f(x)和它对应。 f，使对于集合A中的任意一个元素x，在集合B中都有唯一确定的元素y与之对应。称f:A?B为从集合A到集合名称称f:A?B为从集合A到集合B的一个函数记法

B的一个映射对应f:A?B是一个映射 y?f(x)，x?A 注：函数与映射的区别：函数是特殊的映射，二者区别在于映射定义中的两个集合是非空集合，可以不是数集，而函数中的两个集合必须是非空数集。

二、函数的其他有关概念（1）函数的定义域、值域

在函数y?f(x)，x?A中，x叫做自变量，x的取值范围A叫做函数的定义域；与x的值相对应的y值叫做函数值，函数值{f(x)|x?A}的集合叫做函数的值域

（2）一个函数的构成要素定义域、值域和对应关系（3）相等函数

如果两个函数的定义域相同，并且对应关系完全一致，则这两个函数为相等函数。

注：若两个函数的定义域与值域相同，是否为相等函数？（不一定。如果函数y=x和y=x+1,其定义域与值域完全相同，但不是相等函数；再如y=sinx与y=cosx，其定义域为R，值域都为[-1，1]，显然不是相等函数。因此凑数两个函数是否相等，关键是看定义域和对应关系）

（4）函数的表示方法

表示函数的常用方法有：解析法、图象法和列表法。（5）分段函数

若函数在其定义域的不同子集上，因对应法则不同而分别用几个不同的式子来表示，这种函数称为分段函数。

分段函数的定义域等于各段函数的定义域的并集，其值域等于各段函数的值域的并集，分段函数虽由几个部分组成，但它表示的是个函数。

he first responsibility of the forest, 26th spring area has fully deployed to the fire, has now entered the fire, we have to be on duty, and defend. Determined to overcome paralysis, must not \past, the reduced requirements during the period. To apply strictly the party with the responsibility, must shoulder the responsibility of the Party Secretary in particular, really practice pipes, it can never shuaishouzhanggui, be sure to layer the implementation falls fire responsibility, to ensure that no major forest fires. To adhere to balanced, correctly handle the relationship between fire and project construction, industrial development, to \cond, to speed up the development of six major industries. Promote development in our region, the key is to give full play to resource advantage to build eco-oriented \new engine of economic growth. Firm confidence. Practice has proved that the \central and provincial requirements, and meet the actual da hinggan mountains, through active efforts have been showing a strong momentum of development. So, in the \development, we must be firm in faith, go all out, perseverance, one caught in the end, convinced that Castle is not relaxed, does not reach the target will never give up. Should focus on industrial projects. Project is to accelerate the industrial development of important support and backing. Industrial project construction, my area there are few in number, small size, low level problems. This year, the project as his party has \have to work hard to project construction. Especially effective during short, catching project shall not, slow, dragging not allowed. All localities should conscientiously implement the project leadership system, timetable, roadmap, and coordinate services, tracking the whole process forward, inverted durations, speeding up progress and seek practical results. Poised to break the project build Set challenges, to accelerate the pace of preliminary formalities, the enterprises have difficulties to pull one way and also help in a timely manner to help businesses market, enhance confidence, urging work as soon as possible. To strengthen the project analysis, proper risk analysis and improve project success rates. (Specific to the XX, we still want to make good use of agricultural advantages, relying on the upper reaches of the forest in the fresh air and XXX pure water and other resources, create high-quality, high-grade green food brands, truly reflect the original character. Meanwhile, adhere to the project as the breakthrough to promote economic development around the \chain\on to forming projects, dig potential projects, focus on key projects, actively cultivating the new leading industries and new sources of economic growth). To promote investment. More accurate professional business, and based my industrial base and resources, aimed at national industrial layoutstressed that promoting the comprehensive revitalization should focus on economic construction as the central focus with, pay special attention to grasp the implementation of five development concepts, deepening reform and promoting the all-round opening up, ensuring and improving people's livelihood, strengthen the construction of ecological civilization, \opment mix. To with new development concept measure work, and command action, and training cadres, in implement implementation new development concept in the looking for opportunities, and build highlights, and expand advantage; to full deepening reform, break bound the aspects created vitality of system mechanism obstacles; to active advance full aspects opening, participation \cast Russian Economic Corridor%uarantees and improved livelihood, strongly won poverty battle; to strengthening ecological civilization construction, for sustainable development reserved space, for future generations left sky blue, and to green, and water clear of better homes. We must in-depth implement implementation new development concept, insisted to economic construction for Center, firmly caught development this first priority, absorbed make construction, heart no distractions caught development, speed up development \ndustry\pth implementation \e big engineering\big environment\out of a article quality more high, and benefits better, and structure more excellent of transformation development of road. To strengthen ecological construction. On March 22, the deep restructuring examined and adopted the opinion on perfecting compensation mechanism of ecological protection, proposed to explore the establishment of diversified ecological compensation mechanism, progressive realization of forests, grasslands, wetlands and other areas of focus and key ecological function and other important regional ecological compensation coverage, the ecological advantages of the region will be further highlighted. We need to go green eco-building, as the essential policy, in strict accordance with the State of main function region construction requirements, careful implementation and Xiaoxing ' an mountains forest ecological protection and economirestructuring plan for the construction of sky blue, ... Acts prohibited by picking up the remaining wells in standing timber. To focus on forest resource conservation, increase the acquisition and supervision of cold storage, no buy fruit, encourage support to leading enterprises, workers ' cooperatives as a unit, the contract management of forest resources, the rational protection and utilization of resources. To work actively towards policy aimed from the level of the State Forestry Administration formulated regulations to protect forest resources as soon as possible to achieve law and regulation to protect forest resources. Should focus on forest fire prevention. Fire safety is the first priority【要点名师透析】

一、求函数的定义域 1、确定函数的定义域的原则

（1）当函数y=f(x)用列表法给出时，函数的定义域是指表格中实数x的集合;

（2）当函数y=f(x)用图象法给出时，函数的定义域是指图象在x轴上的投影所覆盖的实数的集合；（3）当函数y=f(x)用解析式给出时，函数的定义域是指使解析式有意义的实数的集合；（4）当函数y=f(x)由实际问题给出时，函数的定义域由实际问题的意义确定。 2、确定函数定义域的依据

（1）若f(x)是整式，则定义域为全体实数；

（2）若f(x)是分式，则定义域为使分式的分母不为零的x取值的集合；（3）当f(x)是偶次根式时，定义域是使被开方式取非负的x取值的集合；（4）当f(x)是非正数指数幂时，定义域是使幂的底数不为0的x取值的集合；

（5）若已知函数f(x)的定义域为[a,b]，其复合函数f(g(x))定义域由不等式a≤g(x)≤b解出; (6)若已知函数f(g(x))的定义域为[a,b]，则f(x)的定义域为g(x)在x∈[a,b]时的值域。 3、例题解析

〖例1〗(1)函数

(A)［-4,1］ (B)［-4,0)

的定义域为( )

(C)(0,1］ (D)［-4,0)∪(0,1］ (2)已知函数f(2x+1)的定义域为(0,1)，求f(x)的定义域.

解析： (1)本题是判断函数的定义域，实际上是求使函数解析式有意义的x的集合，先列出不等式(组)，然后再解不等式(组)，求出解集；(2)注意在对应法则f下，函数f(2x+1)中2x+1 的范围与函数f(x)中x的范围相同.

解答：(1)选D.