9的倒数与18分之5的倒数的积是

已知函数 f（x）={-1/3x+1/6 x属于【0 π/2】 {2x^2/x+1 【1/2,1】 函数 g（x）=asin（π/6x）-2a+2若存在 x1,x2 属于 [0,1] ,使得 f（x1）=g（x2） 成立 ,则实数a 的取值范围 是【1/2,4/3】 为什么 发射地球同步卫星是,可认为先将卫星发射至距地面高度为h的圆形近地轨道上,在卫星经过A点时点火实施变轨进入椭圆轨道,椭圆轨道的近地点为A,远地点为B.在卫星沿椭圆轨道经过远地点B时再 1.__To learn___(learn) English is to use it.这道题为什么要用动词不定式做主语,而不能用动名词learning做主语?2.My father told me practice __makes__(make) perfect.这道题中短语应该是practice doing sth.,可答案为什么 1.--Good afternoon,Madam.______?--No,can you help me plaese?--Yes,Madam.What are you looking for?--I'd like to buy a needle.A.Are you waiting for meB.Would you like anything elseC.Have you been waited onD.What can I do for you2.____has taken away my 1.Someone called Fred is going to call you,aren't you?反义疑问句,为什么后面用aren't you?2.A:Shall me sing Karaoke at the party?B:XXX.a) Yes,I'd love to.b)All right.I'll do that.c) Yes,that's a good idea d)Thank you,the same to you.为什 任何美国英语电影,英文的读后感,要十句话 已知f（x）=sinX+Asin（X+B）,f（x）是偶函数,且最大值是2,求A,B详细过程 函数y=sinx+Asin(x+a),A>0.a属于[0.360).y为偶函数,最大值是2,求A和a, 若关于X的方程1/3X=1与3X+2A=AX的解相同,则A=?交差的 已知函数f(x)=asin(ωx+f)【a>0,w>0,0 方程3X+2a-1=0的解与方程x-2a=0的解互为相反数,求a 英语翻译One day Mozart saw an old blind street-performer playing the violin in a street corner.He recognize the old man was playing one of his composition(乐曲).The old man played for some time but the hat in front of him was still empty-nobody 英语翻译How music affects your moodMusic can not only give you something to sing and dance to,but also can make you feel happier.Studies have shown that music helps to decrease the sign of depression and even helps to relieve pain.Classical music 英语翻译After school one winter day,Jack’s mother told him to go out and play in the snow.“But it’s so cold outside(外面),Mother!”Jack said.“Put on your coat and your hat and your mittens(棒球手套),”his mother said.“You can bu 已知函数f(x)=3sin(2x+π/3),（1）求f(x)的最大值,最小值及对应自变量x的集合（2)若x属于[0,π/2],求最（1）求f(x)的最大值,最小值及对应自变量x的集合（2)若x属于[0,π/2],求最大值和最小值及对应自 英语翻译few people know that Sir George Cayley(1773--1857)has been called the inventor of the airplane,although I prefer to think of him as its grandfather.Cayley made wide anatomical studies of birds and bird flight.From the studies ,Cayley was 求函数y=4－3sin（2x－排／3）的最大值,最小值,并写出求的最大值,最小值时自变量的集合 英语翻译Gail Ann Dorsey is a singer and songwriter.She also plays bass guitar in a band with the English musician Bryan Ferry.She is from Philadelphia.Her family is in the United States,but her home is in south London.Gail Ann lives alone and doe 求函数y=3sin（2x+π/4）使函数取得最大值和最小值的自变量集合 急 y=1-1/2cosπ/3x的最大值,最小值怎样求?最小值是1/2 最大值是3/2y的求法是什么?一直搞不懂 求详细过程 英语翻译在现代标志设计中加入传统文化既本文提到的传统吉祥图案,需要将传统图形“形”的提取和应用把握好,还要注重对传统图案“意”的延伸运用以及对中国传统图案蕴韵的传承与把 1、由于正比例函数y=kx(k为常数,k≠0)中只有一个参数k,故只需______就可求的k的值2、由于一次函数y=kx+b（k,b为常数,k≠0）中有两个参数k,b,需要______________确定两个关于k,b的方程,求的k,b的值.这 英语翻译《丛林故事》这本书让我回味无穷,我已经读好几遍了!这本书讲述了一个人类的婴儿——男孩毛格利——在丛林中被狼群收养,并在棕熊巴鲁、黑豹巴格西拉、巨蟒卡的帮助下长大成 英语翻译景区占地12平方公里,是国际ISO双认证企业、国家AAA风景区.石林峡因峡谷内山峰根根直立,峭立挺拔,宛若片片石林而得名.赏北国石林、观九天飞瀑、游峡谷险峰、寻石林三绝是石林峡 说明理由1.No one tells us ______,so we need your help.A.how we should do B.what should we do C.how to do it D.what to do it2.He ______ the club and ______ its activities.A.took part in ； joined B.joined； took part in C.joined； took a part i 正比例函数Y=KX(K≠0)的图像是经过点( )和点(1,)的一条直线 英语翻译London is a very big city and it is wonderful.You can see many famous building there.The Thames River runs through the city from west to east.So the city has two parts:the South and the North.Inthe North,there are important buildings,shop 英语翻译麻烦大家可以帮我把下面的英语翻译成汉语,全文为：If you love something,set it free.If it comes back to you,it's yours.If it doesn't,it never was.We do not possess anything in this world,least of all other people.We on 1.The plane finally arrived on the airport _________(safe)这道题为什么不能用safely 要用safety?2.The ice on the river is not thick enough for us to skate on.(保持原意)The ice on the river is ________ _________ for us to skate on.这题 1.Most Irish people go to __________ church every Sunday and the church plays _______ important part in people's lives.A.the; the B.a; an C.the; an D./; an 2道英语选择题目,已给出答案,请解释一下为什么选这个.Nick bought a new camera.He _C_ lots of pictures with it.A had taken B has took C has taken D had tookThere was a fire in the street last night,but the firemen _D_ within twenty 英语.It is very kind ____ you to help me with my lessons because it is very difficult ______ me to learn them well A of ;of B of ;for C for; of D for ;for Will you stay at home ____ your sister comes back Sorry,I can't .I have a meeting and have to