题干

3
2
x-
1
2
9
=a0+a1x+a2x2+......+a8x8+a9x9
,其中ak(k=0,1,2,......8,9)都是常数,则a1+2a2+3a3+......8a8+9a9 的值为( )                                             

A:74

B:272

C:72

D:274

上一题 下一题 0.0难度 选择题 更新时间:2017-04-07 11:23:51

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B

同类题3

阅读理解

Dear Mr. Smith,

    I am seeking an opportunity to work with World Destiny as a Computer Systems Manage. My professional experience and my awareness of your high reputation and great achievements have led me to want to work for World Destiny.

    Since 1998 I have focused on computer-system design and training. As Systems Administrator for Newport Museum for the past two years, I have directed accounting, capital campaign and publication production. We designed the system from scratch, developing all applications, policies, procedures, and training programs. I was well prepared for such a challenge by my previous positions as a Systems Support Specialist and MicroComputer Assistant for the Imperial Corporation of America.

    Over the years, I have worked with Novell, using programs including dBase, Wordstarand Microsoft Word. This familiarity with a variety of hardware and software has helped me to get up to speed on nearly any computer with a minimum training period.

    Additional experience in other fields also adds my value to World Destiny. As a Market Research Coordinator for Cushman & Wakefield of California, I not only researched and maintained(维护)a comprehensive database of Silicon Valley, but also produced statistical and written reports that support Cushman & Wakefield' reputation. Previously, I organized companywide annual sales meetings for Qualogy, Inc.

    Mr. Smith, while this experience more than qualifies me to join any number of successful companies, it is my personal goals that lead to my interest in being part of the World Destiny team. I believe my computer, promotional, and organizational skills, fueled by my beliefs, make World Destiny and me right for each other. Can we arrange an interview at your earliest convenience? I will call within the next week to arrange a meeting.

Sincerely,

Beth Henning

同类题5

阅读理解

    I had to knock on the taxi to get his attention. Finally, the driver, a man about 60, looked up from behind the wheel and apologized, “I'm sorry, but I was reading a letter.” He sounded as if he had a cold or a cough.

    Since I was in no hurry, I told him to finish his letter. He shook his head, explaining that he had already read it several times and almost knew it by heart. Curious, I asked whether it was from a child or maybe a grandchild. “This isn't family,” he replied. “though he might just as well have been a regular member of the family. Old Ed and I grew up together.”

    They were always friends. But since he moved away from the neighborhood 30 years ago, it'd generally just been postcards at Christmas time between them. A couple of weeks ago, Ed died. “I should have kept in touch.” He repeated this, more to himself than to me. To comfort him, I said sometimes we just didn't seem to find the time. “But we used to find the time,” he said. “Take a look.” He handed the letter over to me.

    The first sentence “I've been meaning to write for some time, but I've always delayed it.” reminded me of myself. It went on to say that he often thought about the good times they had had together. When I read the part where it said “Your friendship really means a lot to me, more than I can say because I'm not good at saying things like that”, I found myself nodding in agreement.

    We had gone several kilometers and were almost at my hotel, so I read the last paragraph: “So I thought you'd like to know that I was thinking of you.” And it was ended with “Your Old Friend, Tom.”

    “I thought your friend's name was Ed,” I said.

    “I'm Tom,” he explained. “It's a letter I wrote to Ed before I knew he'd died. I never put it in the mailbox. I guess I should have written it sooner.” His face was pale as he wiped his eyes with a handkerchief.

    When I got to my hotel room I didn't unpack right away. I had to write a letter and post it.

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