18.在函数f(x)=x+2的图象上. ∴an+1=an+2. ∴an+1-an=2. ∴{an}是以a1=1为首项.2为公差的等差数列. ∴an=2n-1. (2)由题易知bn==.则Sn=++-++.① Sn=++-++.② ①-②得Sn=+++-+-=+-=-. 则Sn=1-. 查看更多

 

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已知函数f(x)=(x-1)2g(x)=4(x-1),数列{an}是各项均不为0的等差数列,其前n项和为Sn,点(an+1,S2n-1)在函数f(x)的图象上;数列{bn}满足b1=2,bn≠1,且(bnbn+1g(bn)=f(bn)(n∈N).
(1)求an并证明数列{bn-1}是等比数列;
(2)若数列{cn}满足cn,证明:c1c2c3+…+cn<3.

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已知函数f(x)=(x-1)2g(x)=4(x-1),数列{an}是各项均不为0的等差数列,其前n项和为Sn,点(an+1,S2n-1)在函数f(x)的图象上;数列{bn}满足b1=2,bn≠1,且(bnbn+1g(bn)=f(bn)(n∈N).
(1)求an并证明数列{bn-1}是等比数列;
(2)若数列{cn}满足cn,证明:c1c2c3+…+cn<3.

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已知函数f(x)=(x-1)2g(x)=4(x-1),数列{an}是各项均不为0的等差数列,其前n项和为Sn,点(an+1,S2n-1)在函数f(x)的图象上;数列{bn}满足b1=2,bn≠1,且(bnbn+1g(bn)=f(bn)(n∈N).
(1)求an并证明数列{bn-1}是等比数列;
(2)若数列{cn}满足cn,证明:c1c2c3+…+cn<3.

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已知函数f(x)(x1)2g(x)4(x1),数列{an}是各项均不为0的等差数列,其前n项和为Sn,点(an1S2n1)在函数f(x)的图象上;数列{bn}满足b12bn≠1,且(bnbn1g(bn)f(bn)(nN)

(1)an并证明数列{bn1}是等比数列;

(2)若数列{cn}满足cn,证明:c1c2c3cn<3.

 

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已知函数f(x)(x1)2g(x)4(x1),数列{an}是各项均不为0的等差数列,其前n项和为Sn,点(an1S2n1)在函数f(x)的图象上;数列{bn}满足b12bn≠1,且(bnbn1g(bn)f(bn)(nN)

(1)an并证明数列{bn1}是等比数列;

(2)若数列{cn}满足cn,证明:c1c2c3cn<3.

 

 

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