单件流的优点

数列{an}的前n项和Sn=n^2-7n-8,(1) 求{an}的通项公式(2) 求{|an|}的前n项和Tn The victims of the disaster area need more ______(medicine) support 用计较的两个意思造句.1.计算、比较.2.较量、争论. 六级真题听力 错10个选择 7个词语 几分?算个什么水平? 举头望明月,低头思故乡.猜一个成语. 添加怎么造句 加上怎么造句 Please s______ the new student around our school ,Jim.It's intereting ______(make) different kinds of cakes. 用多么 多么造句加上因为所以 三个角都是六十度的三角形是等边三角形吗?理由是什么? 北京正午太阳升到了一年中最高位置的季节是2011年江苏无锡的地理中考题, 等边三角形三个角分别是什么度 过x轴上动点A(a,0)引抛物线y=x^2+1的两条切线过x轴上动点A（a,0）引抛物线y=x2+1的两条切线AP AQ,P Q为切点,设切线AP,AQ的斜率分别为k1,k2 (1)求证：k1k2=-4（2）求证：直线PQ恒过定点,并求出此点坐标 different和the different的区别 different 和 the different 有何区别the twins are in class补一个:They go to a different school 又怎么解释 英语翻译鸠江区“方特杯”迎五一文化旅游活动 除了新东方和派特森,长春哪里有性价比高的精品小班口语寒假集训营? My uncle often plays the piano in his l____time 过点p(-1,-6)的直线l与抛物线y^2=4x交与A、B两点,若|AP|=|BP|.求直线l的斜率 已知点A在抛物线y^2=4x上,过点A作圆C:(x-1)^2+y^2=1的直线AP,AQ交y轴于M,N.P,Q是切点.1.若A（4,4）求PQ直线方程2.若向量AM乘向量AN=-2,求点A坐标 如何证明等边三角形三个内角为60度 等边三角形三个内角的度数都是（）度. He often plays soccer and listen加不加S?to music. 帮我该写动词的第3人称单数的形式有这几个：welcone meet spell have look like think help find give动词的第3人称单数的形式怎样写?>..帮 THINK YOU VERY MUCH! 三人称单数的动词正在进行时动词原形要变吗用中文回答 spare the first 3pedestrians 什么意思 求英文歌 "Never in my widest dreams could I imagine these people are living in such poor conditions." spare the 1.Did you go to the bookshop yesterday?2.Are koalas rare in the world?3.Will yoi watch TV after school?4.What did you do last night 5.Did Tom go swimming last sunday?6.When was kate born?A.I watched TV B.Yes,he did C.She was born in May.D.NO,I didn't 谁有一些好听的英文歌 一节关于团结心理活动课的作文急!