题目

如果a、b同号，那么二次函数y=ax2+bx+1的大致图象是（ ） A．    B．    C．   D． 答案：D【考点】二次函数的图象． 【分析】分a＞0和a＜0两种情况根据二次函数图象的开口方向、对称轴、与y轴的交点情况分析判断即可得解． 【解答】解：a＞0，b＞0时，抛物线开口向上，对称轴x=﹣＜0，在y轴左边，与y轴正半轴相交， a＜0，b＜0时，抛物线开口向下，对称轴x=﹣＜0，在y轴左边，与y轴正半Mr. Strong is a London taxi driver. The following talk is given by him.“I have been a taxi driver     36    nearly ten years. It’s a nice job most of the time. You meet a lot of people. I always work at night,     37    there is too much traffic during the day. I go to work at 5:30 in the afternoon, and I usually     38   between 2:00 and 3:00 in the morning.”“Some     39    things happened late at night.     40    day I was taking a woman home from a party. She had her little dog with her. When we got to her house, she found that she had lost her     41     . So I waited in the car    42     she climbed in through the windows.” “I waited and waited. After half an hour of ringing the bell I decided to find out    43     was going on. I tied the dog to a tree and started to     44    in through the window. The next thing I knew was that the police came. They thought I was a thief.” “Luckily the woman came downstairs. She     45    have gone to sleep and forgotten me and the dog!” 【小题1】A．inB．forC．beforeD．after【小题2】A．ifB．soC．thoughD．because【小题3】A．go homeB．go shoppingC．do sportsD．do housework【小题4】A．sad B．goodC．strangeD．disappointing【小题5】A．The otherB．AnotherC．The othersD．Other【小题6】A．moneyB．bag C．boxD．key【小题7】A．untilB．whileC．sinceD．as soon as【小题8】A．whatB．whichC．whoD．that【小题9】A．driveB．walkC．climbD．run【小题10】A．willB．canC．mayD．must