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问题 填空题
在△ABC中，如果sinA=
3
sinC，B=30°，b=2，则△ABC的面积为______．
答案

：∵在△ABC中，如果sinA=

3
sinC，故a=
3
c．

又∵B=30°，由余弦定理，可得：cosB=cos30°=

3
2
=
a2+c2-b2
2ac
=
4c2-4
2
3
c2
，

解得c=2，故△ABC是等腰三角形，C=B=30°，A=120°．

故△ABC的面积为

1
2
bc•sinA=
3
，

故答案为

3
．

单项选择题

猪苓汤的功用是（）。

A.清心利水养阴

B.利水清热养阴

C.清热益气生津

D.清心益气止淋

E.益气固表止汗
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填空题

根据句意填入单词或短语的正确形式。

1. Few buildings s_______ the earthquake.

2. He was in s_______ of an old friend.

3. She was a_______ at how calm she felt after the accident.

4. The experiment is d_______ to test the new drug.

5. Don't f_______ that you can succeed without hard work.

6. We d_______ the house with some pictures.

7. I don't know to which team he b_______.

8. He bought her a gold watch _______ for her help. (作为报答)

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