等差数列{an}的前n项和为Sn,若S7-S3=12,则S10=
3个回答
30
S7-S3=12,得a7+a6+a5+a4=12
由于是等差数列,所以a5+a6=6
S10=a1+a2+…a10=(a5+a6)*5=30
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