8.“I this year 14 years old, (点拨:在这句话的正上方放一面镜子.中文为:“我今年14岁. .) 查看更多

 

题目列表(包括答案和解析)

(2012•吉林)问题情境
如图,在x轴上有两点A(m,0),B(n,0)(n>m>0).分别过点A,点B作x轴的垂线,交抛物线y=x2于点C、点D.直线OC交直线BD于点E,直线OD交直线AC于点F,点E、点F的纵坐标分别记为yE,yF
特例探究
填空:
当m=1,n=2时,yE=
2
2
,yF=
2
2

当m=3,n=5时,yE=
15
15
,yF=
15
15

归纳证明
对任意m,n(n>m>0),猜想yE与yF的大小关系,并证明你的猜想.
拓展应用
(1)若将“抛物线y=x2”改为“抛物线y=ax2(a>0)”,其他条件不变,请直接写出yE与yF的大小关系;
(2)连接EF,AE.当S四边形OFEB=3S△OFE时,直接写yE与yF的大小关系及四边形OFEA的形状.

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11、王红在电脑中用英文写个人简历时,把其中一句倒排成:则正确的英文为
I this year 14yeas old,

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已知,在x轴上有两点A(a,0),B(b,0)(其中b<a<0),分别过点A,点B作x轴的垂线,交抛物线y=3x2于点C,点D.直线OC交直线BD于点E,直线OD交直线AC于点F.若将点E,点F的纵坐标分别记为yE,yF,则yE
=
=
yF(用“>”、“<”或“=”连接).

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If the figure 6 is composed of 24 equilateral triangles,then how many non-congruent distinct right triangles with vertices on the intersecting points are possible in this figure(  )

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Rescue workers at the San Jose gold and copper mine in northern Chile had reason to sing this week.A small hole drilled into the earth became a passage(通道) to freedom for thirty-three trapped miners.They spent sixty-nine days underground."Never have people been trapped for so long so deeply," says a doctor at NASA, the American space agency, which helped in the rescue.
But the chief medical officer for the miners said most are in good enough health to leave the hospital within a day or so.The first three were released from the hospital Thursday night.
For much of the day the miners relaxed with Chilean President Sebastian Pinera.The thirty-two Chileans and one Bolivian still wore special sunglasses to protect their eyes.
A  partial mine collapse(坍塌) on 5th of August trapped them more than half a kilometer underground.They had to stretch a two-day food supply.For two weeks no one knew if they were alive or dead.
Later, they received supplies(供给) and a video link lowered through drill holes.That link was how Ariel Ticona watched his wife give birth to their daughter.
The miners have apparently agreed to share the money they earn from selling their story.
They have already received gifts of money and travel offers.Edison Pena has been invited to the New York City Marathon and to Graceland, the home of Elvis Presley in Memphis, Tennessee.Mr.Pena described how he ran in the mine tunnels to ease the stress.And he led the miners in singing Elvis songs.
The first miner rescued on Wednesday was Florencio Avalos.The second was Mario Sepulveda, who talked about how the experience tested his faith.He said: "I was with God and I was with the devil, they fought me, but God won.He took me by my best hand, the hand of God."
The last miner up was Luis Urzua.He was the shift leader when his crew became trapped.
Rescuers used a metal cage to pull the miners to safety in less than twenty-four hours -- faster than expected.The rescue capsule was a half-meter wide and known as the Phoenix.
【小题1】How many miners had been rescued according to the report?
A.ThreeB.Sixty-nineC.Thirty-threeD.Thirty-two
【小题2】According to the passage, when the miners were trapped, some of them did the followings except ________.
A.sharing moneyB.Running to ease stress
C.Watching a video showing his wife giving birthD.Singing songs
【小题3】
Edison Pena was invited to Graceland probably because ________________.
A.he ran in the mine tunnel.B.he prayed to God.
C.he led the miners in singing Elvis songs.D.he was the shift leader.
【小题4】
From the passage, we can infer the followings EXCEPT that _______________.
A.Rescue workers were happy about their rescue work.
B.People felt surprised to find the miners safe and sound.
C.People might have been quite worried about the miners’ safety.
D.The trapped miners drilled a small hole themselves to escape.
【小题5】What would be the best title for the report?
A.A mining accident B.Miners saved, safe and sound
C.A difficult rescueD.Miners trapped deep underground

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