4. When you have finished the book, please            it on the shelf.

A. replace          B. devote            C. consider          D. equip

3. Several rounds of air and ground attacks left the whole Bagdad, the capital of Iraq,      .

A. in pieces              B. in ruins            C. in parts                   D. in places

2. The little boy kept on asking his mother to buy a toy car for him, and finally the mother

gave           .

A. in                  B. up                   C. away               D. out

1. In order to prevent the fire spreading, some of the houses nearby had been        before

the firemen arrived.

A. pulled back          B. pulled down    C. brought back    D. burned down

       （3）設的最小值為

2009年深圳市第二實驗學校高三模擬考試三

      （2）當x>0時，證明不等式

      （1）的單調(diào)區(qū)間；

設函數(shù)

21．（本小題滿分14分）

   （2）令，求數(shù)列b_n的最小值。