问题 选择题
函数y=
1
2
x2-lnx的单调递减区间为(  )
A.(-1,1]B.(0,1]C.[1,+∞)D.(0,+∞)
答案

∵y=

1
2
x2-lnx的定义域为(0,+∞),

y′=

x2-1
x

∴由y′≤0得:0<x≤1,

∴函数y=

1
2
x2-lnx的单调递减区间为(0,1].

故选B.

完形填空

Directions: Read the following passage. Answer the questions according to the information given in the passage.

I’m not a fast reader and I don’t read as much as many other people, but reading is something I enjoy. It opens new worlds to me and widens my perspective(洞察力,眼力).

Recently I found Kobo,an online book store that allows me to buy e-books and read them on a device of my choice. I’m a girl living in Indonesia, where e-books are not available and I had to buy physical books from Amazon in the past. There are two problems with it:

Shipping cost. Since I live far away from the United States, it costs a lot to ship a book. Shipping costs almost as much as the book itself.

Shipping time. It takes about three weeks for the books to arrive through postal mail.

Now with Kobo, I can eliminate those two problems. Not only does it cost less time and money to get the books, but also I prefer to read e-books this way than reading physical books. Here are three reasons why:

I can easily bring the books everywhere. Since all the books are in my iPod touch, I can simply put the device into my pocket and bring it everywhere I go.

The size is smaller. The size of the iPod Touch is smaller than a physical book. This makes reading more convenient for me.

I can read in any position I want. The iPod has a light source, so I can read when I am in darkness. This means that I can read in practically any position and condition.

One more advantage I haven’t mentioned is space. Physical books take space, but e-books don’t.

小题1:Why does the author like reading? (no more than 11 words)

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小题2:What are the problems with buying physical books from Amazon? (no more than 9 words)

_____________________________________________________

小题3:How can the author read when she is in darkness? (no more than 6 words)

_____________________________________________________

小题4:What’s the author’s attitude towards e-books? (no more than 1 word)

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填空题