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问题 选择题

函数f（x）=x2-4x+3（　　）

A．在（-∞，+∞）上是减函数

B．在（-∞，4）是减函数

C．在（-∞，0）上是减函数

D．在（-∞，2）上是减函数

答案

由于二次函数f（x）=x2-4x+3的图象的对称轴为 x=2，开口向上，

故函数在（-∞，2）上是减函数，在（2，+∞）上是增函数，

故选D．

完形填空

Bob’s Travel Diary(旅游日记)

Tuesday, July 16th

Today is rained ,so we went to a museum(博物馆).It was   36  boring. I found(发现) a small boy   37  in the corner. He was lost(迷路) and I helped him find   38  father. That

  39 me feel very happy. I didn’t have   40 money for a taxi, so we walked back   41  

the hotel. I was really tired.

Wednesday, July 17th

Today the   42  was cool, so we decided to   43  tennis(网球).We played all morning. It was really fun. We had Sichuan   44  for dinner.  45  was delicious(美味可口的)!

小题1: A. kind of               B. with                C. on

小题2: A. singing               B. going               C. crying

小题3: A. they                 B. his                  C. my

小题4: A. take                 B. made                C. get

小题5:A. some                B. no                   C. any

小题6: A. on                  B. to                     C. with

小题7: A. weather             B. whether              C. bus

小题8:A. go                  B. take                  C. play

小题9: A. bus                 B. car                    C. food

小题10:A. It                   B. He                    C.S he
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单项选择题

下面程序的运行结果是( )。#include＜iostream.h＞class Sample{int x, y;public:Sample() { x=y=0; }Sample(int a, int b) { x=a; y=b; }void (lisp(){cout＜＜"x="＜＜x＜＜",y="＜＜y＜＜end1;}};void main(){Sample s(2,3), *p=&s;p-＞disp();}

A．x=1, y=2

B．x=2, y=4

C．x=2, y=3

D．x=4, y=3
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