为了得到函数y=3sin(2x-π3)的图象，只需把函数y=3sin2x的图象（_爱下问搜题

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问题选择题

为了得到函数y=3sin(2x-

π

3

)的图象，只需把函数y=3sin2x的图象（　　）

A．向左平移

π

3

个长度单位

B．向右平移

π

3

个长度单位

C．向左平移

π

6

个长度单位

D．向右平移

π

6

个长度单位

答案

由于函数y=3sin(2x-

π

3

)=3sin[2（x-

π

6

）]，故只需把函数y=3sin2x的图象向右平移

π

6

个长度单位即可得到函数y=3sin(2x-

π

3

)的图象，

故选D．

单项选择题

能初步完成循环、呼吸等基本生命现象反射调节的部位是

A．脊髓

B．延髓

C．脑桥

D．中脑

E．丘脑

完形填空

完形填空。

                                          How 3D Movies Work   .
     Do you know 3D movies? When you see one, it's like the story  l in front of you, and you are a part ofit. 3D movies are exciting to   2   , but do you
know how3      them, and     4   you need to wear a pair of 3D glasses? To
understand these questions, let's make an easy   5  .
     O Put a finger   6   your eyes.
     O Cover your lef't eye and look at the finger.
     O Cover your right eye and look at the finger.
     What do you see:l The finger you see with your left eye is in a different
position from the one you see with your right eye. This means you get two
images(图像) when you look at   7     _ with both your eyes. To makea 3D
movie, people have to get two images at the same time,   8_ they use two
video cameras.  When playing a 3D movie, they use two projectors (放机)
at the same time.  This brings two images together on the screen. Then, we
use 3D glasses to separate(识别) the two images. One image enters one eye
and   9 enters the other eye.
     Then our brains   10     the two images together. In this way, we get 3D
pictures.

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( )3. A. make
( )4. A. when
( )5. A. examl)le
( )6. A. in front of
( )7. A. everything
( )8. A. because
( )9. A. other
( )10.A. let

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B. see
B. to make
B. why
B, picture
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B. anything
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B. put

C. to happen
C. look
C. making
C. which
C. experiment
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C. and
C. others
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D. happening
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