第一篇:2015高中数学 初高中衔接教程 第九讲 一次分式函数练习 新人教版
第九讲 一次分式函数
【要点归纳】
axb(a,c不同时为0)的函数,叫做一次分式函数。
cxdk(1)特殊地,y(k0)叫做反比例函数;
xaxb(a,c不同时为0)的图象是双曲线,(2)一次分式函数ycxddadax,y(c0)是两条渐近线,对称中心为(,)(c≠0)。
cccc形如y【典例分析】
例1 说明函数y指出它的对称中心。
例2 求函数y
例3 将函数f(x)图象
(1)求g(x)的表达式;
(2)求满足g(x)≤2的x的取值范围。例4 求函数y
3x1的图象可由函数y的图象经过怎样的平移变换而得到,并x1x1x在-3≤x≤-2上的最大值与最小值。1x1的图象向右平移1个单位,向上平移3个单位得到函数g(x)的x3x(x0)的值域。2x1
例5 函数f(x)xa,当且仅当-1<x<1时,f(x)0 x1(1)求常数a的值;
(2)若方程f(x)mx有唯一的实数解,求实数m的值。
例6 已知ya(x0,a0)图象上的点到原点的最短距离为6 x(1)求常数a的值;(2)设ya(x0,a0)图象上三点A、B、C的横坐标分别是t,t+2,t+4,试求出xm。t最大的正整数m,使得总存在正数t,满足△ABC的面积等于
【反馈练习】
1、若函数y=2/(x-2)的值域为y≤1/3,则其定义域为_____________。
2x1的图象关于点_____________对称。x3x93、若直线y=kx与函数y的图象相切,求实数k的值。
x51|x|
4、画出函数y的图象。
x
12、函数y
5、若函数y
6、(1)函数yax1在(-2,+∞)是增函数,求实数a的取值范围。x2ax1的定义域、值域相同,试求出实数a的值; x1ax1(2)函数y的图象关于直线y=x对称,试求出实数a的值。
x1
第九讲 一次分式函数
【典例分析】
例1 向左平移一个单位,再向上平移三个单位,对称中心为(-1,3)例2 分离常数得:y12 在-3≤x≤-2上是减函数,x1 故 x2,ymax3;x3,ymin2
例3(1)g(x)3例4 2;(2)0x1 x113x3yy3;提示:逆求法 由y(x0)得,x0 22x12y1例5(1)a=1(2)m322或0 例6(1)a=6(2)5 提示:利用根的分布先求出 0m6 【反馈练习】
1、x2或x8 提示: 法1:解分式不等式; 法2:图象法。
2、对称中心(-3,-2)
3、k1或
4、略
5、图象法:a1 251
26、(1)a=1(2)a=1
第二篇:初高中英语衔接易错题50例-新人教 做了这么多练习总结的
初高中英语衔接易错题50例
1.Mr Liu _____ come to the party, but perhaps he will go to see her father.A.must B.should C.may D.ought to 【解释】perhaps也许,表示不确定,may也是不确定 2.–Can I help you, sir?--I’d like to buy a TV set.--This way, please.We have many types for you ____.A.to choose B.to choose from C.choose D.to buy 3.There are so many good books in that bookstore that I can hardly know ___ to buy.A.what B.how C.which D.when 4.This straw hat ___ me.A.doesn’t fit for B.isn’t fit C.doesn’t fit D.fits to
【解释】be fit for sb.fit做形容词,所以前面要用be动词
fit sb.fit做动词,所以否定要用助动词
5.–Why not go climbing the mountain today? The weather is so fine.--______.A.So it is B.Why not? C.Because we have many things to do D.No it isn’t.【解释】问句中的why not表示劝诱和建议,而答句中选择why not表示同意或赞成,意为“可以啊,为什么不可以呢”
6.Of course, there are many difficulties before us, but with our efforts everything will be ___.A.right B.easy C.good D.all right 【解释】all right = fine 没事
7.Doing more exercise can help us ___ diseases and give us energy.A.fight B.fight for C.fight at D.fight with 【解释】fight既可以当及物动词又可以不及物
8.He put his shoulder over his car and pushed it, but it ___ move, not ___.A.wouldn’t;even a bit B.didn’t;even a bit C.couldn’t;a bit D.didn’t much 【解释】在这里是wouldn't的一种用法,就是表达物品的性能、功能缺失 9.--Can I help you?--Could you please change the large note for me?--Sorry, sir, I’m ____change at the moment.A.short for B.short C.short with D.short of 10.–So it’s nothing serious, Doctor?
--___.The children will be all right in a day or two.A.Yes B.No, it is C.No D.Yes, it isn’t 11.She felt ___ tired.So she decided to have a good rest.A.not a bit B.a bit of C.not a little D.not a few 【解释】B答案后应接名词,而不是形容词。D后应接可数名词。
A与C之间的区别:not a little=much not a bit 则相反,一点也不
12.In some parts of the country, ___ dies of that illness.A.one out ten children B.ten of one child C.one child in ten D.one for ten children 【?】13.Corn is a plant that doesn’t need ___ rice.A.water as much as B.as much water as C.as many as D.water as many as 14.Today there are far few cowboys, and they ___ live as they did.A.no doubt B.no wonder C.no matter D.no longer 15.When coal burns, part ___ it is left as ashes.A.of B.through C.to D.inside 16.I am afraid that you have given ___ little work to your work.A.much too B.too much C.very much D.how much 17.What he wanted to do was __ his hands of it.A.wash B.to have washed C.washing D.to be washing 【解释】 这是因为what he wanted to do 是 what he wanted himself to do 的省略,是这句的主语从句。英语中规定句子中前面的从句有do 或者do 的某种形式,其后的不定时(短语)省to , 所以该句的表语(to)wash his hands 省去了to.原句是What he wanted to do was(to)wash his hands of it.18.We have worked out the plan and now we must put it into ___.A.fact B.reality C.practice D.deed 【解释】put…into practice固定词组 意思是付诸实践
19.We didn’t plan our art exhibition like that but it ___ very well.A.worked out B.tried out C.went out D.carried out 20.Will you please ___ the sentences and tell me what the difference there is.A.compare to B.compare with C.compare D.comparing 21.People are usually curious about a person from ___ country.A.other B.another C.the other D.the others 22.By comparing notes, we may ___ different opinions and make the best plan.A.choose B.share C.give D.ask for 23.He came here late last night, or ___ , early in the morning.A.rather B.else C.rather than D.not 【解释】or rather的意思是或者是
24.___ this book and tell me what you think of it.A.Look through B.Look on C.Look into D.Look up 25.In the dark street, there wasn’t a person ___ she could turn for help.A.that B.who C.from whom D.to whom 【解释】turn to sb.for help 26.–We haven’t heard from her for a long time.--What do you suppose ___ to her? A.was happening B.to happen C.has happened D.having happened 27.–What made you so surprised?--___ my house ___ saying good-bye.A.Jim’s leaving;without B.Jim leaving;without C.Jim’s left;instead of D.Jim’s leaving;instead of
28.The fire spread through the hotel very quickly but everyone __ get out.
A.had B.would C.could D.as able to 29.I should I like to ___ you and your men by the hand, and thank each of you personally for all you have done.A.thank B.love C.shake D.greet 30.The little boy has a great ___ for language: he can speak three foreign languages very well.A.present B.gift C.joy D.interest 31.I bought a pair of new shoes which is very similar ____ a pair I had before.A.with B.to C.about D.on 32.He made another wonderful discovery, ___ of great importance to science.A.which I think is B.which I think it is C.which I think D.I think which is 33.We should ___ the great man with the title of the National Hero.A.honor B.offer C.give D.name 34.Would you ___ to us why you would like to give up such a good job? A.show B.explain C.tell D.discuss 35.His careless driving ___ him his life last year.A.cost B.spent C.paid D.took 36.With her dearest jewels ___ , she was almost mad.A.missed B.gone C.being stolen D.were lost 37.On her way home, she found her handbag ___.A.being lost B.missing C.losing D.has gone 38.Helen ___ a Chinese for almost twenty years.A.has married to B.has married C.has been married to D.has been married with 39.I’ll ___ my first teacher’s home tomorrow.A.call for B.call at C.call in D.call on 40.This house is worth 1,000 yuan ___.A.more and less B.after all C.at the most D.at the presant 41.They were the first people ___ in this vast farmland.A.living B.to live C.lived D.live 42.Such difficult experiments ___ you did that day need much patience ___ imagination.A.like;as well as B.as;as well as C.for;as well D.like;as well 43.All the experiments __ by Miss Lu were highly praised.A.conducted B.conducting C.conduct D.had conducted 44.All these ideas may seem strange to you, but scientists are working hard to ___ them one by one in time.A.come true B.realize C.make D.produce 45.He must have got the book yesterday, ___ he ? A.mustn’t B.haven’t C.hasn’t D.didn’t
46.The farmer got the tractor ____ in the field all the day.A.to work B.worked C.working D.work
47.They wear winter clothes to ___ themselves ___ bad cold.A.prevent;against B.keep;from C.stop;/ D.protect;from 48.Have you see a horse ___ the pole over there? A.tying at B.tied by C.tied to D.tied with 49.I you ___ the nature in farming, you will do more work and get less harvest.A.go against B.go with C.work after D.do against 50.Each team scored twice and the game ____.A.put an end B.ended in a tie C.made an end C.ended up
参考答案
1--10 CBCCB DAADC 11--20 CCBDA AACAC 31--40 BAABA BBCBC 41--50 BBABD CDCAB
21--30 BBAAD CADCB
第三篇:11-12学年高中数学 1.2.1 几个常用的函数的导数同步练习新人教A版选修2-2
选修2-2
1.2
第1课时
几个常用的函数的导数
一、选择题
1.下列结论不正确的是()
A.若y=0,则y′=0
B.若y=5x,则y′=5
C.若y=x-1,则y′=-x-2
[答案] D
2.若函数f(x)=,则f′(1)等于()
A.0
B.-
C.2
D.[答案] D
[解析] f′(x)=()′=,所以f′(1)==,故应选D.3.抛物线y=x2在点(2,1)处的切线方程是()
A.x-y-1=0
B.x+y-3=0
C.x-y+1=0
D.x+y-1=0
[答案] A
[解析] ∵f(x)=x2,∴f′(2)=li
=li
=1.∴切线方程为y-1=x-2.即x-y-1=0.4.已知f(x)=x3,则f′(2)=()
A.0
B.3x2
C.8
D.12
[答案] D
[解析] f′(2)=
=
=
(6Δx+12)=12,故选D.5.已知f(x)=xα,若f′(-1)=-2,则α的值等于()
A.2
B.-2
C.3
D.-3
[答案] A
[解析] 若α=2,则f(x)=x2,∴f′(x)=2x,∴f′(-1)=2×(-1)=-2适合条件.故应选A.6.函数y=(x+1)2(x-1)在x=1处的导数等于()
A.1
B.2
C.3
D.4
[答案] D
[解析] ∵y=x3+x2-x-1
∴=
=4+4Δx+(Δx)2,∴y′|x=1=li
=li[4+4·Δx+(Δx)2]=4.故应选D.7.曲线y=x2在点P处切线斜率为k,当k=2时的P点坐标为()
A.(-2,-8)
B.(-1,-1)
C.(1,1)
D.[答案] C
[解析] 设点P的坐标为(x0,y0),∵y=x2,∴y′=2x.∴k==2x0=2,∴x0=1,∴y0=x=1,即P(1,1),故应选C.8.已知f(x)=f′(1)x2,则f′(0)等于()
A.0
B.1
C.2
D.3
[答案] A
[解析] ∵f(x)=f′(1)x2,∴f′(x)=2f′(1)x,∴f′(0)=2f′(1)×0=0.故应选A.9.曲线y=上的点P(0,0)的切线方程为()
A.y=-x
B.x=0
C.y=0
D.不存在[答案] B
[解析] ∵y=
∴Δy=-
=
=
∴=
∴曲线在P(0,0)处切线的斜率不存在,∴切线方程为x=0.10.质点作直线运动的方程是s=,则质点在t=3时的速度是()
A.B.C.D.[答案] A
[解析] Δs=-=
=
=
∴li
==,∴s′(3)=
.故应选A.二、填空题
11.若y=x表示路程关于时间的函数,则y′=1可以解释为________.
[答案] 某物体做瞬时速度为1的匀速运动
[解析] 由导数的物理意义可知:y′=1可以表示某物体做瞬时速度为1的匀速运动.
12.若曲线y=x2的某一切线与直线y=4x+6平行,则切点坐标是________.
[答案](2,4)
[解析] 设切点坐标为(x0,x),因为y′=2x,所以切线的斜率k=2x0,又切线与y=4x+6平行,所以2x0=4,解得x0=2,故切点为(2,4).
13.过抛物线y=x2上点A的切线的斜率为______________.
[答案]
[解析] ∵y=x2,∴y′=x
∴k=×2=.14.(2010·江苏,8)函数y=x2(x>0)的图像在点(ak,a)处的切线与x轴的交点的横坐标为ak+1,其中k∈N*,若a1=16,则a1+a3+a5的值是________.
[答案] 21
[解析] ∵y′=2x,∴过点(ak,a)的切线方程为y-a=2ak(x-ak),又该切线与x轴的交点为(ak+1,0),所以ak+1=ak,即数列{ak}是等比数列,首项a1=16,其公比q=,∴a3=4,a5=1,∴a1+a3+a5=21.三、解答题
15.过点P(-2,0)作曲线y=的切线,求切线方程.
[解析] 因为点P不在曲线y=上,故设切点为Q(x0,),∵y′=,∴过点Q的切线斜率为:=,∴x0=2,∴切线方程为:y-=(x-2),即:x-2y+2=0.16.质点的运动方程为s=,求质点在第几秒的速度为-.[解析] ∵s=,∴Δs=-
==
∴li
==-.∴-=-,∴t=4.即质点在第4秒的速度为-.17.已知曲线y=.(1)求曲线在点P(1,1)处的切线方程;
(2)求曲线过点Q(1,0)处的切线方程;
(3)求满足斜率为-的曲线的切线方程.
[解析] ∵y=,∴y′=-.(1)显然P(1,1)是曲线上的点.所以P为切点,所求切线斜率为函数y=在P(1,1)点导数.
即k=f′(1)=-1.所以曲线在P(1,1)处的切线方程为
y-1=-(x-1),即为y=-x+2.(2)显然Q(1,0)不在曲线y=上.
则可设过该点的切线的切点为A,那么该切线斜率为k=f′(a)=.则切线方程为y-=-(x-a).①
将Q(1,0)坐标代入方程:0-=(1-a).
解得a=,代回方程①整理可得:
切线方程为y=-4x+4.(3)设切点坐标为A,则切线斜率为k=-=-,解得a=±,那么A,A′.代入点斜式方程得y-=-(x-)或y+=-(x+).整理得切线方程为y=-x+或y=-x-.18.求曲线y=与y=x2在它们交点处的两条切线与x轴所围成的三角形的面积.
[解析] 两曲线方程联立得解得.∴y′=-,∴k1=-1,k2=2x|x=1=2,∴两切线方程为x+y-2=0,2x-y-1=0,所围成的图形如上图所示.
∴S=×1×=.
第四篇:高中数学:2.1.4《函数的奇偶性》教案(新人教B必修1)
2.1.4 函数的奇偶性 学案
【预习要点及要求】 1.函数奇偶性的概念;
2.由函数图象研究函数的奇偶性; 3.函数奇偶性的判断;
4.能运用函数奇偶性的定义判断函数的奇偶性; 5.理解函数的奇偶性。【知识再现】
1.轴对称图形:
2中心对称图形: 【概念探究】
1、画出函数f(x)x,与g(x)x的图像;并观察两个函数图像的对称性。
2、求出x3,x2,x
结论:f(x)f(x),g(x)g(x)。
3、奇函数:___________________________________________________
4、偶函数:______________________________________________________ 【概念深化】(1)、强调定义中“任意”二字,奇偶性是函数在定义域上的整体性质。(2)、奇函数偶函数的定义域关于原点对称。
5、奇函数与偶函数图像的对称性:
如果一个函数是奇函数,则这个函数的图像是以坐标原点为对称中心的__________。反之,如果一个函数的图像是以坐标原点为对称中心的中心对称图形,则这个函数是___________。
如果一个函数是偶函数,则这个函数的图像是以y轴为对称轴的__________。反之,如果一个函数的图像是关于y轴对称,则这个函数是___________。
6.根据函数的奇偶性,函数可以分为____________________________________.【例题解析】
例1.已知f(x)是奇函数,且当x0时,f(x)x2x,求当x0时f(x)的表达式
例2.设为实数,函数f(x)x|xa|1,xR,讨论f(x)的奇偶性
参考答案:
例1.解:设x0,则x0,f(x)(x)2(x)x2x,又因为f(x)为奇函数,2222321时的函数值,写出f(x),g(x)。2 f(x)f(x),f(x)(x2x)x2x
当x0时f(x)x2x
评析:在哪个区间上求解析式,x就设在哪个区间上,然后要利用已知区间的解析式进行代入,利用f(x)的奇偶性,把f(x)写成f(x)或f(x),从而解出f(x)
例2.解:当a0时,f(x)(x)|x|1x|x|1f(x),所以f(x)为偶函数
当a0时,f(a)a1,f(a)a2|a|
1此时函数f(x)既不是奇函数,也不是偶函数
评析:对于参数的不同取值函数的奇偶性不同,因而需对参数进行讨论 达标练习:
一、选择题
1、函数f(x)x22222222x的奇偶性是()
A.奇函数 B.偶函数 C.非奇非偶函数 D.既是奇函数又是偶函数
2、函数yf(x)是奇函数,图象上有一点为(a,f(a)),则图象必过点()
A.(a,f(a))B.(a,f(a))C.(a,f(a))D.(a,二、填空题:
1)f(a)
3、f(x)为R上的偶函数,且当x(,0)时,f(x)x(x1),则当x(0,)时,f(x)___________.4、函数f(x)为偶函数,那么f(x)与f(|x|)的大小关系为 __.三、解答题:
5、已知函数f(x)是定义在R上的不恒为0的函数,且对于任意的a,bR,都有f(ab)af(b)bf(a)
(1)、求f(0),f(1)的值;
(2)、判断函数f(x)的奇偶性,并加以证明。= 参考答案:
1、C;
2、C;
3、x(x+1);
4、相等; 5.(1)f(0)f(00)0f(0)0f(0)0f(1)f(11)f(1)f(1),f(1)0(2)f(1)f[(1)2]f(1)f(1)0f(1)0,f(x)f(1x)f(x)f(1)f(x)f(x)为奇函数.课堂练习:教材第49页 练习A、第50页 练习B 小结:本节课学习了那些内容? 请同学们自己总结一下。课后作业:第52页习题2-1A第6、7题
第五篇:(新课程)高中数学 2.1.1《函数》教案 新人教B版必修1
2.1.1函数 教案(2)
教学目标:理解映射的概念;
用映射的观点建立函数的概念.教学重点:用映射的观点建立函数的概念.教学过程:
1.通过对教材上例
4、例
5、例6的研究,引入映射的概念.注:1,补充例子:投掷飞标时,每一支飞标射到盘上时,是射到盘上的唯一点上。于是,如果我们把A看作是飞标组成的集合,B看作是盘上的点组成的集合,那么,刚才的投飞标相当于集合A到集合B的对应,且A中的元素对应B中唯一的元素,是特殊的对应.同样,如果我们把A看作是实数组成的集合,B看作是数轴上的点组成的集合,或把A看作是坐标平面内的点组成的集合,B看作是有序实数对组成的集合,那么,这两个对应也都是集合A到集合B的对应,并且和上述投飞标一样,也都是A中元素对应B中唯一元素的特殊对应.一般地,设A,B是两个集合,如果按照某种对应法则f,对于集合A中的任何一个元素,在集合B中都有唯一的元素和它对应,那么这样的对应(包括集合A,B以及A到B的对应法则f)叫做集合A到集合B的映射,记作f:A→B.其中与A中的元素a对应的B中的元素b叫做a的象,a叫做b的原象.2,强调象、原象、定义域、值域、一一对应和一一映射等概念 3.映射观点下的函数概念 如果A,B都是非空的数集,那么A到B的映射f:A→B就叫做A到B的函数,记作y=f(x),其中x∈A,y∈B.原象的集合A叫做函数y=f(x)的定义域,象的集合C(CB)叫做函数y=f(x)的值域.函数符号y=f(x)表示“y是x的函数”,有时简记作函数f(x).这种用映射刻划的函数定义我们称之为函数的近代定义.注:新定义更抽象更一般
1(x是有理数)如:f(x)(狄利克雷函数)(0x是无理数) 4.补充例子:
例1.已知下列集合A到B的对应,请判断哪些是A到B的映射?并说明理由:
⑴ A=N,B=Z,对应法则:“取相反数”;
⑵A={-1,0,2},B={-1,0,1/2},对应法则:“取倒数”; ⑶A={1,2,3,4,5},B=R,对应法则:“求平方根”;
00⑷A={|090},B={x|0x1},对应法则:“取正弦”.例2.(1)(x,y)在影射f下的象是(x+y,x-y),则(1,2)在f下的原象是_________。
2(2)已知:f:xy=x是从集合A=R到B=[0,+]的一个映射,则B中的元素1在A中的原象是_________。
(3)已知:A={a,b},B={c,d},则从A到B的映射有几个。
【典例解析】
例⒈下列对应是不是从A到B的映射,为什么?
⑴A=(0,+∞),B=R,对应法则是"求平方根";
x2⑵A={x|-2≤x≤2},B={y|0≤y≤1},对应法则是f:x→y=(其1
中x∈A,y∈B)
2⑶A={x|0≤x≤2},B={y|0≤y≤1},对应法则是f:x→y=(x-2)(其中x∈A,y∈B)
x⑷A={x|x∈N},B={-1,1},对应法则是f:x→y=(-1)(其中x∈A,y∈B).
例⒉设A=B=R,f:x→y=3x+和-3的原象.
6,求⑴集合A中112和-3的象;⑵集合B中22
参考答案:
例⒈解析:⑴不是从A到B的映射.因为任何正数的平方根都有两个,所以对A中的任何一个元素,在B中都有两个元素与之对应.⑵是从A到B的映射.因为A中每个数平方除以4后,都在B中有唯一的数与之对应.⑶不是从A到B的映射.因为A中有的元素在2B中无元素与之对应.如0∈A,而(0-2)=4B.⑷是从A到B的映射.因为-1的奇数次幂是-1,而偶数次幂是1.∴⑴⑶不是,⑵⑷是.
[点评]判断一个对应是否为映射,主要由其定义入手进行分析.
1115和x=-3分别代入y=3x+6,得的象是,-3的象是-3; 222111
1⑵将y=和y=-3,分别代入y=3x+6,得的原象-,-3的原象226例⒉解:⑴将x=是-3.
[点评]由映射中象与原象的定义以及两者的对应关系求解. 课堂练习:教材第36页 练习A、B。
小结:学习用映射观点理解函数,了解映射的性质。课后作业:第53页习题2-1A第1、2题。