题目

20. 已知函数的图象过点P（0，2），且在点M（-1，f（-1））处的切线方程为.（Ⅰ）求函数的解析式；（Ⅱ）求函数的单调区间. 答案：20.本小题主要考查函数的单调性、导数的应用等知识，考查运用数学知识分析问题和解决问题的能力. 解：（Ⅰ）由的图象经过P（0，2），知d=2，所以由在处的切线方程是，知故所求的解析式是（Ⅱ）解得  当当故内是增函数，在内是减函数，在内是增函数.短文填空. We know that trees are useful in our everyday life. They ________ us many things, such as wood, rubber(橡胶), medicine and many other things. They can ________ tell us a lot about our climate. The following are the reasons(理由). If you ________ across a tree, you can see that it has many rings. Most trees grow one new ring ________ year. Because of the reason, we know ________ a tree is. A tree over a hundred years old means that it has more than a hundred ________ . When the climate is not much rainy or very cold, the trees do not grow very much and their rings are usually ________ . When it is wet and warm, the rings are not thin. If the rings are suddenly very thin or suddenly very thick(厚), this means that the ________ changes suddenly. If we look at the rings on this tree, we can learn ________ the climate for a hundred years. We can see________ our climate changed. From trees we can get a lot. So we should pay attention to them as much as possible.【1】A. tell B. ask C. give D. get【2】A. not B. too C. to D. also【3】A. cut B. climb C. walk D. see【4】A. every B. many C. the first D. from【5】A. how big B. how long C. how old D. how much【6】A. trees B. leaves C. people D. rings【7】A. big B. long . small D. thin【8】A. climate B. trees C. rings D. animals【9】A. from B. of C. about D. to【10】A. how B. why C. when D. while