对于定义域为A的函数f(x),如果任意的x1,x2∈A,当x1<x2时,都有f(

题型:解答题

问题:

对于定义域为A的函数f(x),如果任意的x1,x2∈A,当x1<x2时,都有f(x1)<f(x2),则称函数f(x)是A上的严格增函数;函数f(k)是定义在N*上,函数值也在N*中的严格增函数,并且满足条件f(f(k))=3k.

(Ⅰ)证明:f(3k)=3f(k);

(Ⅱ)求f(3k-1)(k∈N*)的值;

(Ⅲ)是否存在p个连续的自然数,使得它们的函数值依次也是连续的自然数;若存在,找出所有的p值,若不存在,请说明理由.

考点:函数的奇偶性、周期性
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工业上用于大批量制造铁基粉末冶金零部件的铁粉包括哪两类?它们在制造零部件时各有什么优缺点?

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As a high school athletics coach, I gave a speech about football to students and parents, aiming at getting new team members :I talked  about how"everyone  can benefit from football. This year, a worried-looking couple approached me. Their son, who had a sickly childhood, really wanted to play football. They'd tried to talk him out of it, but he had his heart set on joining the team.

When they told me his name , my heart sank. Michael was short and thin. He was a lonely kid and the constant target of other kids' jokes. I knew Michael would never make it. But so close to my  "football is for everyone"  speech,  I told them we could give it a try.

On the opening day of practice, Michael was the first player on the field. We started a one-mile jog around the track. Repeatedly he fell, each time picking himself up. The same thing happened for weeks. But Michael put his whole heart into the training. Cradually, Michael gained strength both socially and physically. He began to laugh and most of the teammates became friendly. By the last week of practice Michael could run the mile without falling. He asked me to add a few more exercises he could work on his own. Soon ,  Michael ran the opening mile faster than anyone.

One day after practice, the team captain, Steve, came up to me. He was talented but lazy.He was popular with students even though he could be heartless. Steve pointed to the field where Michael was jogging all alone and asked me why he was still out there. I told Steve to ask him. The next night, I was surprised to see Steve exercising right next to Michael.

Finally our big game came-at first we were losing by twelve points. I could see that some kids  had already lost heart. But Michael was playing as hard as he could ,  begging the team to keep trying. Finally we won the game by one point in the final ten seconds.

At our celebration dinner, we always gave a big award to the most productive player. Steve had scored the most points that season,  and everyone cheered as he received his award. " There's someone who deserves it more than I do,"  Steve said,  " Everything I accomplished,  and everything the team accomplished this season, is thanks to one person-Michael. " The entire team cheered as Steve turned the prize over to the player who had inspired them all.

小题1:The author gave a speech to the students and parents in order to ____.

A.bring in new team members

B.teach them how to play football

C.tell them about the benefits of playing football

D.help those parents who are worried about their children小题2:How did the author react after the couple told him their son's name?

A.He was very excited about accepting Michael on the team.

B.He refused to accept Michael because he had no talent for sports.

C.He decided to accept Michael though he was unwilling to do so.

D.He agreed to accept Michael because he was moved by his determination.小题3: What happened to Michael after a few weeks' training?

A.He gave up training.

B.He began to laugh at others.

C.He often protected others in the football field.

D.He became strong both in friendly relations and in body.小题4: Which of the following can be the best title for the passage?

A.The Road to Success

B.Heart of a Champion

C.Steve, the Real Winner

D.A Player of Patience

题型:解答题

缺少油脂,含水量少,干枯,蓬散,不容易定型的头发称为()。

A.硬发

B.绵发

C.天然卷发

D.沙发

题型:解答题

下列不属于旋流器常用给料方式的是()。

A、定压给料

B、物料泵送,介质定压给料

C、泵送给料

D、无压给料

题型:解答题

某梁纵向受力钢筋为5根直径为20mm的HRB335级钢筋(抗拉强度为300N/mm2),现在拟用直径为25mm的HPB300级钢筋(抗拉强度为270N/mm2)代换,所需钢筋根数为()。

A.3根

B.4根

C.5根

D.6根

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