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已知数列{an}及其前n项和Sn满足:a1=3,Sn=2Sn-1+2n(n≥2,n∈N*)...
试题详情
已知数列{a
n}及其前n项和S
n满足:a
1=3,S
n=2S
n-1+2
n(n≥2,n∈N*).
(1)证明:设b
n=
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABEAAAAxCAYAAAA8wULMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAAFISURBVEhL7VZbDsQgCORk3MnreBmP4lFYUNui
thWSfuyryWabVEdmBgGgBx54AIMeBkmBAKD+QuIAE8WYTYG2SBIFCLytPQ2wYBmeCpIjIUbS56ag
QBdAKhIgNIY/Yh7CbppYOSik3h2htQtrEKMtmS0uQEgeZpBjGDaIU0AeVpDClhfaXrszsgtKQulE
c1IpIHb5rlcuQKo+UBJRv/eA9yA5U2aqGPkeIetUnJv1WtIR4ZEBiuWi3YltBjrIdtdbJYBn1t+D
6JMvqCzd6U6+uVtLTSwp8G0ge3HeirTzf+mORdQ/yLlKH5NsP1zZpgFHNbKtHt5WNvnYLTxGDHNl
yyl1w02O2PqM9fqddUChNkxNK7gpYyUS78Q0gHByOaOY6oln2NMU90iEhmewmUFK066tsvVLFyCP
W2zpVJydk9LKPsv39ylKL33y/Rr6MY91AAAAAElFTkSuQmCC
)
,{b
n}是等差数列;
(2)求S
n及a
n.
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