已知Sn是数列{an}的前n项和，a1=1，a2=3，数列{anan+1}是公比为2的等比数列，则S10=

题干

已知S_n是数列{a_n}的前n项和，a₁=1，a₂=3，数列{a_na_n₊₁}是公比为2的等比数列，则S₁₀=（）

A：1364

B： $\frac{124}{3}$

C：118

D：124

上一题下一题 0.0难度选择题更新时间:2018-01-28 04:26:21

D

A

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Feel stressed	Too much homework. Don't have enough time for their hobbies.	Make a plan for study and hobbies. Find time to relax.
Get short sighted (近视)	Too much homework. Bad study habits.	Do homework or read in a correct way.
Fight with each other	Don't know how to get on well with classmates.	Make more friends and understand each other.
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Get fat	Have more pocket money to buy snacks. Don't like to do exercise.	Use your pocket money to do something meaningful. Do exercise every day.