设正项等比数列{an}的前n项和为Sn，且210S30+S10=（210+1）S

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设正项等比数列{a_n}的前n项和为S_n，且2¹⁰S₃₀+S₁₀=（2¹⁰+1）S₂₀，则数列{a_n}的公比______．

答案

设数列{a_n}的公比为q，因为2¹⁰S₃₀+S₁₀=（2¹⁰+1）S₂₀，

所以，2¹⁰（S₃₀-S₂₀）=（S₂₀-S₁₀），由此可得2¹⁰（S₂₀-S₁₀）q¹⁰=（S₂₀-S₁₀），

所以，q¹⁰=(

)10．又因为{a_n}是正项等比数列，所以q=

．

故答案为：

．

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Man has invented four kinds of satellites. The first kind of satellite studies the__1__of the earth. They are used to make maps. They also help countries to see where they may__2___ oil or gold. The second kind of satellite is used to guide ships and planes. A ship or a plane can _3__a message to the satellite, and the satellite can find out __4___ the ship or the plane is.
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选择题

已知热化学方程式(Q₁，Q₂均为正值)：C(s)＋O₂(g)=CO(g)　ΔH＝－Q₁kJ·mol^－1，C(s)＋O₂(g)=CO₂(g)　ΔH＝－Q₂ kJ·mol^－1，有关上述反应的叙述错误的是（）

A．Q₁＜Q₂

B．生成物总能量均高于反应物总能量

C．由1 mol C反应生成1 mol CO气体时放出Q₁ kJ热量

D．1 mol CO₂气体具有的能量大于1 mol干冰具有的能量

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