问题 填空题

定义在R上的运算:x*y=x(1-y),若不等式(x-y)*(x+y)<1对一切实数x恒成立,则实数y的取值范围是    

答案

∵(x-y)*(x+y)=(x-y)(1-x-y)

=x-x2-y+y2

<1,

∴-y+y2<x2-x+1,要使该不等式对一切实数x恒成立,则需有-y+y2<(x2-x+1)min=,

解得-<y<.

完形填空

Zhang Lili is a Chinese language teacher at No. 19 Middle School of Jiamusi in Heilongjiang Province. And now people think she is the most beautiful teacher in China.

At 8:38 pm on Tuesday, May 8th,2012, Zhang Lili and her students were crossing a road when a school bus ran to them. Without any hesitation (犹豫), she pushed two students out of the way, but she was then run over and her own legs were found under the wheels. The 29-year-old teacher lost her legs.

Jin Yanping, head teacher of No. 19 Middle School, Jiamusi City said, “She’s the most popular teacher among the students. For the students, she is a sister. They call her ‘Beautiful Sister’.”

But Zhang Lili is more than a teacher and sister to the 53 students in her class. She cares about their studies and even their lives.

A student’s parent said, “She is very warm-hearted. My son has lost his father. Every month, the teacher gives him 100 yuan to buy books, with her own salary(工资)。”

But, for her family, anxiously waiting outside the ICU room(重症监护室),they just want her to live.

Li Ziye, Zhang Lili’s husband, said, “All our family want her to live, then we can get over any difficulty, as long as our family is complete.”

小题1:What subject does Zhang Lili teach?

                                                                         

小题2:Were Zhang Lili and her students crossing a road when a school bus ran to them?

                                                                         

小题3:What did Zhang Lili lose?

                                                                         

小题4:What do Zhang Lili’s students call her ?

                                                                         

小题5:Zhang Lili cares not only students’ studies but also their lives, doesn’t she?

                                                                         

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