已知数列{an}的首项a1=1,前n项之和Sn满足关系式:3tSn+1-(2t+3)Sn=3t(t>0,n∈N*).(1)求证:数列{an}是等比数列;(2)设数列{an}的公比为f(t),数列{bn}满足bn+1=f(1bn),(n∈N*),且b1=1.
<p>问题:已知数列{an}的首项a1=1,前n项之和Sn满足关系式:3tSn+1-(2t+3)Sn=3t(t>0,n∈N*).(1)求证:数列{an}是等比数列;(2)设数列{an}的公比为f(t),数列{bn}满足bn+1=f(1bn),(n∈N*),且b1=1.<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">林建勇的回答:<div class="content-b">网友采纳 (1)证明:∵3tSn+1-(2t+3)Sn=3t,∴3tSn-(2t+3)Sn-1=3t,(n≥2),两式相减得3tan+1-(2t+3)an=0,又∵t>0,∴an+1an=2t+33t(n≥2),当n=2时,3tS2-(2t+3)S1=3t,即3t(a1+a2)-(2t+3)a1=3t,且a1=1...
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