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数列{an}的首项a1=1,{bn}为等比数列且bn=an+1an,若b50b51=2016150,则a101=()A.2015B.4030C.2016D.4032

题目详情

数列{an}的首项a1=1,{bn}为等比数列且bn=

an+1
an
,若b50b51=2016 
1
50
,则a101=(  )

A. 2015

B. 4030

C. 2016

D. 4032

▼优质解答
答案和解析
由bn=an+1an,且a1=1,得b1=a2a1=a2.b2=a3a2,a3=a2b2=b1b2.b3=a4a3,a4=a3b3=b1b2b3.…an=b1b2…bn-1.∴a101=b1b2…b100.∵数列{bn}为等比数列,∴a101=(b1b100)(b2b99)…(b50b51)=(b50b51)50(2016150)5...