Sn等差数列,S3比S6等于1/3,则S6比S7等于多少

Sn等差数列,S3比S6等于1/3,则S6比S7等于多少 设Sn是等差数列An的前n项和,若S3/S6=1/3,则S6/S12等于 设Sn是等差数列{an}的前n项和,若S3/S6=1/4,则S6/S12等于? 设Sn是等差数列{an}的前n项和,若S3/S6=1/3,则S6/S12等于—— 设Sn是等差数列『An』的前n项和,诺S3/S6＝1/3,则S6/S12的值等于 设Sn是等差数列an的前n项和,若S3/S6=1/3,则S6/S7=? Sn是等差数列an前n项和,若S3/S6=1/3,则S6/S12=? 设Sn是等差数列{An}的前n项和,若S3/S6=1/3,则S6/S12=? 设Sn是等差数列的前n项和,S3:S6=1:3,则S6:S9= 设Sn是等差数列{an}的前n项和,若S3/S6=1/3,则S6/S12=? 设Sn是等差数列an前n项和 若S3/S6=1/3则S6/S12正确的做法我知道 但我这种做法怎么错了Sn成等差 所以S3,S6-S3,S12-S6也成等差因为S3/S6=1/3,所以S6-S3=2S3,所以S12-S6=3S3所以S12=6S3 所以S6/S12=1/2 已知等比数列{an}的前n项和为Sn,若S3,S9,S6成等差数列,则 A S6=-1/2xS3 B S6=-S3 C S6=1/2xS3 D S6=2S3 设Sn是等差数列an的前n项和,若S3/S7=1/3,则S6/S7= 设sn是等差数列前n项和,若s3/s6=1/3则s6/s12=?答案是3/10 设Sn是等差数列｛an｝的前N项和,诺S3/S6=1/3则S6/S12=多少 等差数列an的前n项和为sn若s6/S3=3,则s9/S6=? 设等差数列{an}的前n项和为Sn,若S6/S3=3,则S9/S6=? 设Sn是等差数列{an}的前n项和,若S3/S6=1/3,求S6/S12