已知数列an的前n项和为sn,4sn=an^2+2an-3,若a1,a2,a3成等比数列,且n大于等于3时a大于0.(1)求证当n大于等于3时,an成等差(2)求an前n项和sn
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![已知数列an的前n项和为sn,4sn=an^2+2an-3,若a1,a2,a3成等比数列,且n大于等于3时a大于0.(1)求证当n大于等于3时,an成等差(2)求an前n项和sn](/uploads/image/z/1741079-47-9.jpg?t=%E5%B7%B2%E7%9F%A5%E6%95%B0%E5%88%97an%E7%9A%84%E5%89%8Dn%E9%A1%B9%E5%92%8C%E4%B8%BAsn%2C4sn%3Dan%5E2%2B2an-3%2C%E8%8B%A5a1%2Ca2%2Ca3%E6%88%90%E7%AD%89%E6%AF%94%E6%95%B0%E5%88%97%2C%E4%B8%94n%E5%A4%A7%E4%BA%8E%E7%AD%89%E4%BA%8E3%E6%97%B6a%E5%A4%A7%E4%BA%8E0.%EF%BC%881%EF%BC%89%E6%B1%82%E8%AF%81%E5%BD%93n%E5%A4%A7%E4%BA%8E%E7%AD%89%E4%BA%8E3%E6%97%B6%2Can%E6%88%90%E7%AD%89%E5%B7%AE%EF%BC%882%EF%BC%89%E6%B1%82an%E5%89%8Dn%E9%A1%B9%E5%92%8Csn)
已知数列an的前n项和为sn,4sn=an^2+2an-3,若a1,a2,a3成等比数列,且n大于等于3时a大于0.(1)求证当n大于等于3时,an成等差(2)求an前n项和sn
已知数列an的前n项和为sn,4sn=an^2+2an-3,若a1,a2,a3成等比数列,且n大于等于3时a大于0.(1)求证当n大于等于3时,an成等差(2)求an前n项和sn
已知数列an的前n项和为sn,4sn=an^2+2an-3,若a1,a2,a3成等比数列,且n大于等于3时a大于0.(1)求证当n大于等于3时,an成等差(2)求an前n项和sn
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