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共回答了17个问题采纳率：94.1% 举报
6(a1+a6)/2=s6
3(a1+a3)/2=s3
because 4s6=11s3
24(a1+a6)=33(a1+a3)
24a1-33a1+24a6-33a3=o
because a6-a3=1
thus -9a1-9a3+24=0
24-18a2=0
solve a2,3a2=s3,s6 can be solved too,and then u will see how to do it
what a boring day~
i wanna back to china!
1年前
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