已知等差数列{an}的前n项和为Sn,且满足S33-S22=1,则数列{an}的公差是(  ) A.12 B.1 C.2 D.3

问题描述:

已知等差数列{an}的前n项和为Sn,且满足

S3
3
-
S2
2
=1,则数列{an}的公差是(  )
A.
1
2

B. 1
C. 2
D. 3

S3=a1+a2+a3=3a1+3d,S2=a1+a2=2a1+d,

S3
3
-
S2
2
=
d
2
=1
∴d=2
故选C