已知等差数列{an}的前几项和为Sn,且满足s3比3-S2比2=1则数列{an}的公差是几

问题描述:

已知等差数列{an}的前几项和为Sn,且满足s3比3-S2比2=1则数列{an}的公差是几
二分之一?1

S3 = 3a1+3d
S2 = 2a1+d
所以,
S3/3 - S2/2 = d/2 = 1
所以,
d=2