已知等差数列{an}的前n项和为Sn,公差d≠0,且S3+S5=58,a1,a3
题型:解答题
问题:
已知等差数列{an}的前n项和为Sn,公差d≠0,且S3+S5=58,a1,a3,a7成等比数列.
(I)求数列{an}的通项公式;
(II)若{bn}为等比数列,且b5•b6+b4•b7=a8,记Tn=log3b1+log3b2+…+log3bn,求T10值.
已知等差数列{an}的前n项和为Sn,公差d≠0,且S3+S5=58,a1,a3,a7成等比数列.
(I)求数列{an}的通项公式;
(II)若{bn}为等比数列,且b5•b6+b4•b7=a8,记Tn=log3b1+log3b2+…+log3bn,求T10值.