EXCEL,我想B1=A1+A2+A3,B2=A4+A5+A6,B3=A7+A8+A9...怎么做

2024-12-01 12:53:31
推荐回答(2个)
回答1:

∵数列{an}为等差数列,∴a1+a2+a3,a4+a5+a6,a7+a8+a9构成等差数列,∴a7+a8+a9=9+2×18=45,故选B

回答2:

sum(offset(a$1,row()*3-3,,3)