（1）请写出一个各项均为实数且公比0＜q＜1的等比数列，使得其同时满足a1+a6=11且a3•a4=
（2）在符合（1）条件的数列中，能否找到一正偶数m，使得am，
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（1）由条件可知a1，a6应该是方程x2-11x+
=0的两个根，32 9
解得
或 a1= 1 3 a6= 32 3
，继而得到q=2或q= a1= 32 3 a6= 1 3
，（4分）1 2
所以符合条件的等比数列可以是an=
•2n-1（公比q＞1舍去），（3分）1 3
或an=
•(32 3
)n-1=1 2
•26-n(n∈N*)，符合条件（3分）1 3
（2）对于an=
•(32 3
)n-1=1 2
•26-n（3），1 3
由2
=am-a 2m
，（2分）1 9
解得m=7或m=6．（2分）
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| Antarctica (南极洲) is the continent which is the most southern area of land on the Earth and is mostly covered with ice. This is one of the driest and 1 in the world. But people from all over the world come to 2 there. Near the South Pole, three thousand people live together in a place 3 Amundsen-Scott Station. The station has libraries, cinemas, shops, sports rooms, canteens and laboratories. There is electricity, and they have 4 — the system that they use to have a conversation with someone in another place. And they have 5 — electronic machines that stores information and uses programs to help them find, organize, or change the information. But the people here 6 travel by car, or train, or bus, because there aren't any roads or railways near the station. They travel by ship, helicopter, plane, or snow tractor, or 7 dogs. There aren't 8 trees or flowers there, but there are hundreds of different birds and other animals. Most of the people here are 9 . They study plant and animal life and how ice moves. The ice can tell us about changes in climate. Ray Kingman is an expert at Amundsen-Scott Station, telling us on the phone, "This is my second year here. It's a very interesting and beautiful place, but life is very hard 10 . In the summer we can go swimming in hot pools of water. We welcome newcomers here for further study of the continent!" | ||||||
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