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问题 填空题

设a，b是方程x2+2x-2015=0的两个实数根，则a2+3a+b的值为______．

答案

∵a是方程x2+2x-2015=0的根，

∴a2+2a-2015=0，即a2+2a=2015，

∴a2+3a+b=a2+2a+a+b=2015+a+b，

∵a，b是方程x2+2x-2015=0的两个实数根，

∴a+b=-2，

∴a2+3a+b=2015-2=2013．

故答案为2013．

填空题

单词拼写。

1. It is very important to know your own strengths and w______.

2. He pushed against that big stone with all his s______.

3. After all these years we have paid off all our d______.

4. Chocolate can offer you some e______ when you are tired or hungry.

5. Vegetables are rich in v______.

6. I ______ (咨询) a doctor about my pains.

7. It takes hours for a meal to ______ (消化).

8. He didn't shout or swear, but just ______ (怒视) silently at me.

9. No fishing is allowed within a twenty-mile ______ (界限).

10. "I wish I didn't have so much to do." she ______ (叹息).

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单项选择题

关于肺结核治疗效果的评价，以下不正确的是（）.

A.结素试验可协助判断病情

B.临床治愈时，空洞仍可存在

C.临床治愈时，病灶内仍可残留结核菌

D.痰菌阴转为考核疗效的主要指标

E.临床治愈则不再有咯血
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