问题
选择题
已知数列{an}中,a1=1,2nan+1=(n+1)an,则数列{an}的通项公式为( )
|
答案
∵2nan+1=(n+1)an,
∴
=an+1 n+1
•1 2
,an n
∴数列{
}是等比数列,首项an n
=1,公比为a1 1
.1 2
∴
=(an n
)n-1,1 2
∴an=
.n 2n-1
故选:B.
已知数列{an}中,a1=1,2nan+1=(n+1)an,则数列{an}的通项公式为( )
|
∵2nan+1=(n+1)an,
∴
=an+1 n+1
•1 2
,an n
∴数列{
}是等比数列,首项an n
=1,公比为a1 1
.1 2
∴
=(an n
)n-1,1 2
∴an=
.n 2n-1
故选:B.