题目

若函数的定义域为，则实数取值范围是（   ） A．         B．                 C．          D． 答案：A试题分析：由于函数的定义域为，所以在上恒成立，即方程至多有一个解，所以，解得，则实数取值范围是.完形填空（共20小题；每小题1.5分，满分30分） 阅读下面短文，掌握其大意，然后从各题所给的A、B、C、D四个选项中，选出最佳选项。 I have never learned as much math in my life as I did last year, It was because of Ms. Pam  21    I truly understood what I was learning. It might not seem  22     a big deal to some，but to me it is. I have never met a woman so caring and so determined to teach her  23  . I never really wanted to work for good   24   in math class. I never knew how to study math and never understood some of the concepts. I can remember trying to sneak (偷偷溜出) the classroom    25    Ms. Pam caught me and yelled across the   26   ," Lauren, are you coming to extra help during lunch?" It was a nightmare… She would always  27  me with one foot out of the door; it never   28  . Even then I just thought of it as a thing I had to do. It was funny to see how everyone would be in her room during lunch and then again after school. She would  29  everyone to come every day，just so we could do our homework in  30  . Many of the students thought of her as a bit of nag (唠叨)，but  31  they knew that she was right and   32   for it. Many of her tests were hard at first，but as the year progressed，many students felt them easier，so did I. I knew that it was because of her. Even outside class，she was  33  as ever. She always wanted to know what was going on in my（and everyone else’s）life，and she was always looking out for everyone’s best interest.     Ms. Pam is a sweet woman with a sense of   34   that you just have to laugh at. When regents were approaching，she was more concerned than ever about everyone doing well. Many of her precious students   35  high，and so she  36  the same from us. Day after day there were students in the classroom   37   problems. When it was time for our big test，I knew I was ready. I walked out of that test with my head  38 . I knew that I was a  39  and Ms. Pam had made me that way, I appreciated all the hard work that she put into helping me and my fellow students. I knew that I would  40  her. 21. A. how                     B. what                   C. that                        D. why 22. A. like                           B. as                        C. so                           D. as if 23. A. students               B. children         C. classmates            D. family 24. A. life                         B. salary                C grades             D. subjects 25. A. while                              B. unless                  C. before                         D. until 26. A. seat                  B. classroom         C. yard                 D. kitchen 27. A. see                                 B. catch                  C. help                              D. beat 28. A. succeeded               B. stopped              C. worked             D. failed 29. A. encourage            B. let                         C. forbid                   D. hope 30. A. confusion                      B. peace                             C. surprise                      D. home 31. A. inside                             B. outside              C. almost                       D. hardly 32. A. praised              B. scolded               C. respected                   D. blamed 33. A. frightened            B. caring                  C. hard                 D. right 34. A. duty                  B. time                  C. foolishness              D. humour 35. A. jumped                          B. scored            C. grew                           D. drank 36. A. hoped                      B. received              C. wished                    D. expected 37. A. previewing                 B. making                 C. learning                      D. reviewing 38. A. low                                    B. hanging         C. high                        D. down 39. A. failure                            B. student              C. success                       D. hero 40. A. hate                           B. miss                C. forget                         D. marry