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问题 解答题

若关于x的不等式（2x-1）2＜ax2的解集中整数恰好有3个，则实数a的取值范围是______．

答案

∵不等式等价于（-a+4）x2-4x+1＜0，

当a≥4时，显然不满足要求，

故4-a＞0且△=4a＞0，

故0＜a＜4，

不等式的解集为

1
2+
a
＜x＜
1
2-
a
，
1
4
＜
1
2+
a
＜
1
2

则一定有1，2，3为所求的整数解集．

所以3＜

1
2-
a
≤4，

解得a的范围为(

25
9
，
49
16
]

故答案：(

25
9
，
49
16
]

填空题

Part 4


Questions 26-45


·Read the following text and decide which answer best fits each space.
·For questions 26-45, mark one letter A, B, C or D on the Answer Sheet.

Speaking Her Hind


By the time they turn 55, most Hollywood actresses see their careers start to fade. Not (26) for Susan Sarandon, who will help kick offthe fall movie season with three films.
(27) of the movies are likely to be blockbusters, but Sarandon chooses her (28) more for the stories they tell (29) for their commercial potential. "If we’re very lucky, these films will (30) questions that people will talk about," she says.
She’s done her own share of questioning, and arrived at a place in life (31) she’s not afraid to stand (32) her convictions—and then follow (33) with action. The eldest of nine children in a New Jersey Roman Catholic family, she stumbled into an acting (34) when she attended an audition with her ex-husband, Chris Sarandon. Twenty-five years and five Oscar nominations later, she (35) a Best Actress Academy Award for her role as Sister Helen Prejean in 1995’s Dead Man Waling, a searing film about capital punishment.
By (36) Sarandon was practiced at using her celebrity to (37) causes close to her heart. (38) , while presenting an award at the 1993 Oscars, she and longtime partner Tim Robbins, an actor and director, took 30 seconds of their podium time to speak on (39) of Haitian refugees with AIDS. "At the (40) of acting and activism is imagination," Sarandon says. "I’ve (41) had the ability to imagine being in someone else’s shoes."
She is a supporter of end-hunger and poverty (42) including Heifer International, Madre, and Habitat for Humanity, as (43) as the Center for Constitutional Rights. In the aftermath of September 11, she cooked for workers at Ground Zero, did benefit performances, and befriended firefighters and victims’ families.
Sarandon is (44) hands-on in the role she calls her (45) important—mother of three children.

A．some

B．that

C．now

D．then
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单项选择题

由汉至唐使用的牒是（）。

A.上行公文

B.平行公文

C.下行公文

D.无固定指向公文
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