1.若数列an满足:a1=1,a(n+1)=2an(n∈N+),则a5=?前8项的和S8=?2.等差数列an的前n项和为Sn,且S3=6,a1=4,则公差d?3.设等比数列an的前n项和为Sn ,若S6/S3=3,则S9/S6=4.已知等比数列an的公比为正数,且a3*a9=2a5^2,a2=1,

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1.若数列an满足:a1=1,a(n+1)=2an(n∈N+),则a5=?前8项的和S8=?2.等差数列an的前n项和为Sn,且S3=6,a1=4,则公差d?3.设等比数列an的前n项和为Sn ,若S6/S3=3,则S9/S6=4.已知等比数列an的公比为正数,且a3*a9=2a5^2,a2=1,

1.若数列an满足:a1=1,a(n+1)=2an(n∈N+),则a5=?前8项的和S8=?2.等差数列an的前n项和为Sn,且S3=6,a1=4,则公差d?3.设等比数列an的前n项和为Sn ,若S6/S3=3,则S9/S6=4.已知等比数列an的公比为正数,且a3*a9=2a5^2,a2=1,
1.若数列an满足:a1=1,a(n+1)=2an(n∈N+),则a5=?前8项的和S8=?
2.等差数列an的前n项和为Sn,且S3=6,a1=4,则公差d?
3.设等比数列an的前n项和为Sn ,若S6/S3=3,则S9/S6=
4.已知等比数列an的公比为正数,且a3*a9=2a5^2,a2=1,则a1=
5.等比数列an的公比q>0,已知a2=1,a(n+2)+a(n+1)=6an,则an的前4项和S4
6.等差数列an的公差不为零,首项a1=1,a2是a1和a5的等比数列,S10=
7.设a1=2,a(n+1)=1/a(n+1),bn=(an)+2/(an)-1的绝对值,n∈N+,则数列bn的通项公式
7.设a1=2,a(n+1)=2/a(n+1),bn=(an)+2/(an)-1的绝对值,n∈N+,则数列bn的通项公式

1.若数列an满足:a1=1,a(n+1)=2an(n∈N+),则a5=?前8项的和S8=?2.等差数列an的前n项和为Sn,且S3=6,a1=4,则公差d?3.设等比数列an的前n项和为Sn ,若S6/S3=3,则S9/S6=4.已知等比数列an的公比为正数,且a3*a9=2a5^2,a2=1,
1.16 255
2.-2
3.7/3
4.根号2/2
5.3.5
6.100
7.有问题吧.

1.a5=16 s8=255
2.-2
3.7/3
4.√2/2
5.3.5
6.100