【简答题】“Well, we’re in our new house. Let’s get a new pet to go along with it,” Mrs. Brown said to her husband. “That sounds like a very good idea,” he answered. “Do you want to see the ads in the newspaper?...
【简答题】(13分) 已知曲线 C : 的横坐标分别为1和 ,且 a 1 =5,数列{ x n }满足 x n +1 = tf ( x n – 1) + 1(t > 0且 ).设区间 ,当 时,曲线 C 上存在点 使得 x n 的值与直线 AA n 的斜率之半相等. (1) 证明: 是等比数列; (2) 当 对一切 恒成立时,求 t 的取值范围; (3) 记数列{ a n }的前 n 项和...
【简答题】用所给单间的适当形式填空. 1. He told he _____ (help) her with her maths the next evening. 2. She said they _____ ( know) each other for quite sometime. 3. If it _____ (not rain) tomorrow, we _____ (visit) the Peo...