9.Pop music is liked by many people, but it is not _____ everyone’s taste.
A.with B.in C.on D.to
8.We are kept ____ of what is happening in the world by reading newspapers and watching television.
A.to inform B.to be informen C.informing D.informed
7.It was the first time that he______ a game, so he felt very sad.
A.loses B.lost C.has lost D.had lost
6.The girl got married ______ the man who she had been engaged _______.
A.with; with B.to; to C.with; to D.to; in
5.--- Didn’t you have a good time at the party?
---- Of course I did.As a matter of fact, I had such fun that time seemed to _____ so quickly.
A.go by B.go away C.go out D.go over
4.When he came to,he found himself _____ by a group of villagers.
A.surrounding B.being surrounded
C.surrounded D.surround
3._____ you have bought!
A.What a fine piece of furniture B.How fine furniture
C.what a fine furniture D.How beautiful a furniture
2.His words surprised everyone.I couldn’t _____ so.
A.imagine his saying B.think him saying
C.imagine him to say D.consider him saying
第一节:单项填空(共35小题;每小题1分,满分35分)
从A、B、C、D四个选项中,选出可以填人空白处的最佳选项,并在答题卡上将该项涂黑。
1.---I don’t believe it’s good to hang the drawing here.
---- _______ I move it over there? Do you think it will look better?
A.What about B.What if C.How about D.What with
15.在(2x-3y)10的展开式中,求:
(1)二项式系数的和;
(2)各项系数的和;
(3)奇数项的二项式系数和与偶数项的二项式系数和;
(4)奇数项系数和与偶数项系数和;
(5)x的奇次项系数和与x的偶次项系数和.
解:设(2x-3y)10=a0x10+a1x9y+a2x8y2+…+a10y10(*)
各项系数和即为a0+a1+…+a10,奇数项系数和为a0+a2+…+a10,偶数项系数和为a1+a3+a5+…+a9,x的奇次项系数和为a1+a3+a5+…+a9,x的偶次项系数和a0+a2+a4+…+a10.
由于(*)是恒等式,故可用“赋值法”求出相关的系数和.
(1)二项式系数和为C+C+…+C=210,
(2)令x=y=1,各项系数和为(2-3)10=(-1)10=1.
(3)奇数项的二项式系数和为C+C+…+C=29.
偶数项的二项式系数和为C+C+…+C=29.
(4)设(2x-3y)10=a0x10+a1x9y+a2x8y2+…+a10y10
令x=y=1,得到a0+a1+a2+…+a10=1①
令x=1,y=-1(或x=-1,y=1)
得a0-a1+a2-a3+…+a10=510②
①+②得2(a0+a2+…+a10)=1+510,
∴奇数项的系数和为;
①-②得2(a1+a3+…+a9)=1-510,
∴偶数项的系数和为.
(5)x的奇次项系数和为a1+a3+a5+…+a9=;
x的偶次项系数和为a0+a2+a4+…+a10=.
湖北省互联网违法和不良信息举报平台 | 网上有害信息举报专区 | 电信诈骗举报专区 | 涉历史虚无主义有害信息举报专区 | 涉企侵权举报专区
违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com