(文)如图,已知双曲线x2a2-y2b2=1,F1,F2分别是它的左、右焦点,P

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问题:

(文)如图,已知双曲线
x2
a2
-
y2
b2
=1
,F1,F2分别是它的左、右焦点,P2P⊥F1F2,交双曲线于P点,连接F1P交双曲线于另一点Q,分别与双曲线的渐近线交于A,B,且∠F1PF2=60°.
(1)求双曲线的离心率;(2)求
|PQ|
|AB|
的值.
考点:双曲线的性质(顶点、范围、对称性、离心率)圆锥曲线综合
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政府价格决策听证的组织部门是( )。

A.国务院办公厅
B.政府价格主管部门
C.国务院财政厅
D.政府价格监管部门

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具有抗厌氧菌作用的抗生素是

A.氧氟沙星

B.头孢哌酮

C.头孢氨苄

D.头孢他定

E.甲硝唑

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葡萄中含有丰富的白藜芦醇(C14H12O3),它具有抗癌性能,可抑制癌细胞的增生.下列有关白藜芦醇的说法正确的是(  )

A.它由14个碳元素、12个氢元素和3个氧元素构成

B.它由碳、氢、氧三种元素组成的

C.该物质中,碳、氢、氧三种元素的质量比为14:12:3

D.它的相对分子质量为228g

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石膏模两个显著的缺点是强度不高和耐热性能差。

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Losing a job or not being able to find one almost always brings unwelcome changes. If you’’ve lost a job, the first feeling is often one of shock. On top of the loss of income, many people find the whole routine of their life is shattered, their contact with other people reduced, their ambitions halted and their identity as a worker removed.There may be good feelings too — it’’s nice to be able to lie in bed in the morning, to spend more time with children, or to have more time to think — a better job may be just around the corner. But, unless a better job does turn up, chances are the days start getting longer and the time becomes harder to fill. Many people pass through periods of difficulty in sleeping and eating. They feel irritable and depressed, often isolated and lonely.Despite all these problems, unemployment can be a chance for a fresh start. You can discover that it provides an opportunity to sort out or rethink what you want from life and how best you can get it. You can use the time to plan how to find a new job, learn a new skill, develop your hobbies, see if you can run your own business, do some voluntary work in your community or meet new people. It’’s up to you.

According to the passage, when a person has first lost a job, more often than not, he feels________.

A.excited

B.isolated

C.shocked

D.depressed

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