七年级科学同步辅导

已知关于x的方程ax+3=3a+x有无数个解,说明关于x的方程a(x-2)=ax+2的解的情况 解关于x方程2分之ax=3分之-x+1 当a=?时,方程a-1分之ax-x-1分之2=1的解与方程x分之x-4=3的解相同 高一数学--偶函数f(x)对任意实数x,y恒有f(x+y)=f(x)+f(y)-2xy-1,则函数f（x）的表达式偶函数f(x)对任意实数x,y恒有f(x+y)=f(x)+f(y)-2xy-1,则函数f（x）的表达式__________让我看懂~】【十分感谢】 已知函数f（x）是在定义域上的偶函数,对任意实数x都有xf（x+1）=（1+x）f（x）,求f（2分之五） 用英语介绍你最喜欢的季节,为什么?(不少于十句话) 用英语介绍自己家10句以下可以抽象如:Zhoujielun is I father ..... 方程x的平方+3x+m中的m是什么数值时,方程的两个实数根满足 1：一个根比另一个根大二2 一个根是另一个根的三倍 已知函数f(x)=2x^2-3x+1,g(x)=Asin(x-π/6)(A>0),当o 有关X的方程(m-1)X的平方-3X-4=0 当方程有两实数根时m取值范围// 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