四川乐山市高中1994届数学(理工农医类)第一次调研考试试题及解答

一、选择题：（每小题4分，共68分）（1的值是（C）(A)1/4(B)1/8(C)3/4(D)3/8（2）若A＝｛x│x2-2x-3＜0｝，B＝｛x│lg(x 1）＜1｝,则A∩B为（D）（A)｛x│x≤-1｝∪｛x│3≤x≤9｝（B）｛x｜－1＜x＜3}（C)｛x｜－1＜x＜9｝（D)｛x｜3≤x＜9｝（3）如图，长方体ABCD－A'B'C'D'中，BB’＝BC，直线A’C和直线BC’的位置关系是（C）（A）互相垂直的相交直线（B）不互相垂直的相交直线（C）互相垂直的异面直线（D）不互相垂直的异面直线（4）过点（l，2），且与原点距离最大的直线方程是(A)（A）x＋2y－5＝0（B）2x＋y－4＝0…     

直线y=kx＋b（k≠0）之极值在实际中的应用

对于直线y=kx＋b（k≠0）本身无最值可言（用于实际问题）,但是当我们对一次函数直线y=kx＋b的定义域加以限定（m≤x≤n）则可通过k的符号由一次函数的增减性而取其最值,即     

用直线系方程解题

1．经过定点的直线系方程 经过定点M（x0,y0）的直线y-y0=k·（x-x0）（k为参数）是一束直线（不包括与y轴平行的那一条x=x0）,所以y-y0=k（x-x0）（是为参数）是通过定点M（x0,y0）的直线系方程．     

利用函数图象解五类问题

一、求函数的最值及值域 例 1.求函数 y=的最大值与最小值 . 解：令 u=， v=则有 u2＋ v2=20,y=2u＋ v,在同一坐标系内画出四分之一个圆： u2＋ v2=20和直线系： v=－ 2u＋ y的图象 .如图 1，直线与圆相切时，有 ymax=OA.直线过点 B(0， 2 )时，有， ymin=OB.∴ ymax=10.ymin=2 . 例 2.求函数 y=2x－ 2 的值域 . 解：把给定函数变形为－ 2x＋ y=－ 2 ,令 y=t，得－ 2x＋ t=－ 2. .在同一坐标系中分别作出直线系 y=－ 2x＋ t及半双曲线 y=－ 2的图象 .如图 2直线系 y=－ 2x＋ t与下半双曲线 y=－ 有交点时， t≤－ 4或 0 二、比较大小 例 3…     

与过定点直线相关的一类问题韵处理

直线是解析几何的基础,在解题时经常遇到一些特殊的过定点的直线,如过定点肘（x0,y0）的直线系方程为y—y0=五（x-x0）及x=xn;过直线l1：a1x＋b1y＋c1=0和l2：a2x＋b2y＋c2=0的交点的直线系的方程为（a1x＋b1y＋c1）＋λ（a2x＋b2y＋c2）=0（不含l2）．定点只是一个特殊点,但不要忽视它,定点若是运用得好,在解题中会起到意想不到、事半功倍的效果．     

用解析几何求磁场中的曲线方程

1．参数法 题1如图1所示,在0≤x≤2a,-a≤y≤a的某一区域存在一匀强磁场,方向垂直纸面向里．在直线y=a的上方,直线x=0与x=2a之间的区域内,有一沿y轴负方向的匀强电场,     

巧用过交点的曲线系方程解题

设二曲线方程分别为C1：f（x,y）=0,与C2：g（x,y）=0,则过二曲线C1、C2交点的曲线系方程为：f（x,y）＋λg（x,y）=0（不含曲线g（x,y）=0）。利用这一方程解答直线与圆的有关考题,可化拙为巧、化难为易。例1 求过二直线l1：3x＋4y-5=0和l2：2x-3y＋8=0的交点,且满足下列条件的直线l的方程：     

一道一次函数与反比例函数综合题的多种解法

例如图1,直线y=4/3x与双曲线y=k/x（x〉0）交天点A,将直线y=4/3x赂下平移个6单位后,与双曲线y=k/x（x〉0）交于点B,与x轴交于点c,     

他山之石，可以攻玉——也谈一道高考题的另解

题（2009安徽理科20）点P（x0,y0）在椭圆x^2/b^2＋y^2/b^2=1（a＞b＞0）上,x0=acosβ,y0=bisnβ,0＜β＜∏/2,直线ι2与直线ι1：x0/a^2x＋y0/b^2y=1垂直,0为坐票原点,直线0P的倾斜角为a,直线ι2的倾斜角为γ.     

关于一阶微分方程的初值问题的一点注记

1.问题的提出 我们来看下列问题的举例及解答。 例1 设第一象限内的曲线y=y（x）对应于0≤X≤a一段的长等于曲边梯形0≤y≤y（x）,0≤x≤a的面积,a>0是任给的,y（O）=1,求y（X） （参注释[2]p32.11.5131） 编者在答案与提示中给出; y=chx 例2 在上半平面求一条向上凹的曲线,其上任一点P（x.y）处的曲率等于此曲线在该点的法线段PQ长度的倒数（Q是法线与x轴的交点）。且曲线在点（1,1）处的切线与x轴平行。（参注释[2]P317,11.5.5全国硕士研究生统考题） 解:曲线y=y（x）在点（x,y）处的法线方程是     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.