来自靖涛的问题
(2011•合肥二模)巳知数列{an}的前n项和Sn,满足:S2=3,2Sn=n+nan,n∈N*,数列{bn}是递增的等比数列,且b1+b4=9,b2•b3=8,(1)求数列{an}、{bn}的通项公式;(2)求和Tn=a1b1+a2b2+…+anbn.
(2011•合肥二模)巳知数列{an}的前n项和Sn,满足:S2=3,2Sn=n+nan,n∈N*,数列{bn}是递增的等比数列,且b1+b4=9,b2•b3=8,
(1)求数列{an}、{bn}的通项公式;
(2)求和Tn=a1b1+a2b2+…+anbn.
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2020-11-18 02:09