终止子序列

若（ax²-3x）（x²-2x-1）的展开式中不含x³项,则a= 要使（ax²－3x）(x²－2x-1)的展开项式中不含x³项,则a=______ 方程和算术法阿阿阿阿阿 要使（ax²-3x）（x²-2x-1)的展开式中不含x³项,则a= 4（20+a)-4(20-a） 要有方程和算术法噢, (-2x)²×（3x²-ax-6)-3x³+x²中不含x的三次项,求a的值 一道数学题,提问时间一周以内回答!有两个点（牛）,下有一条直线（河）,要在河旁建一个草场（在直线上做点）,怎么才能使这个点与两头牛之间的距离 总和 最短?沙发你确定对吗？能不能 1+2+3+4到200 改为否定句：We were having a PE class at four yesterday afternoon.改：We __ __a PE class at four yesterday afternoon. 1.We were having a P.E class at four yesterday afternoon.(改为否定句)1.We were having a P.E class at four yesterday afternoon.(改为否定句)2.Kate was reviewing her lessons at 8 last night. 对（8 last night 算术法或方程解,甲、乙两辆汽车分别从A、B两地同时相对开出,乙车每小时行全程的10％,甲车比乙车早小时到达A、B两地的中点,当乙车到达中点时,甲车又继续向前行驶了25千米到达C点,A、B两 急用!用算术法,东东和红红同时开始上楼,红红到达4楼用了240秒,东东到达7楼用了300秒．那么当红红到达6楼时,东东在第几楼? 不能用方程解,只能用算术法 1.一个乒乓球从25米的高空下落,每次弹起的高度是下落高度的2/,它第四次下落后又能弹起多少米?2.某年七月份雨天是晴天的2/3,阴天是晴天的2/5,这个月晴天有几天?3.仓库有一批化肥,运出它的4/ 200 40 40 20怎么运算等于202 5+10+15+20+.+195+200等于多少 While the family were inside,the Beckham's assistant took the eight-month-old dog for a walk翻译 1.while,took,we,down,were,off,walking,the UFO,the street2.was,called,buying,the police,a souvenir,the alien,when,the girl3.the alien,saw,the girl,shopping,get,when,out,she,was4.had,very,experience,Sunday,unusual,I,last,a5.the plane,raining,in,was,whe while the police were coming Linda walk around the station最快的速度帮我完成 拜托····· What were you doing yesterday afternoon when I was watching TV.这句话中when可以换成while吗 翻译：While we were watching the play ,I suddenly noticed a man with a funny look . 已知函数y=lg(x+1)/x-1的定义域 What were you doing _______ A yesterday Bthis time yesterdayB不用加THE吗？ 翻译：昨天晚上的这个时候你在做什么? what were you doing at this time yesterday evening 还是what were you doing this time yesterday evening What were you doing at this time yesterday?怎么回答 4÷2=20÷10=120÷60=400÷200……求从左往右，被除数和除数 商不变。从右往左，被除数和除数 商不变。用字母a、b、m、n（都不为0）表示发现的性质（字母要全用上） 这个性质的用途之一是（用 What were you doing this time yesterday?若强调部分是what怎么写强调句还有类似的I wonder what you were doing this time yesterday.(强调what）What John said disappointed all hie classmate.(强调disappointed) 计算并观察：2的平方=4,20的平方=400,200的平方=40000,2000的平方4000000有什么规律 What were you doing this time yesterday?-I on the grass and drawing a picture.A.sit B.sat C.am sitting D.was sitting 如图 ：△ABC的边AB,AC为边分别向外作正方形ABDE和正方形ACFG,连接EG,试判断△ABC和△AEG的面积关系,并说明理由. 1.一件商品原价1000元,先降价10分之1后,再涨价10分之1,这件商品的现价是多少元?