(10*10+11*11+12*12+13*13+14*14)⼀365=

2025-01-02 09:17:38
推荐回答(3个)
回答1:

(10*10+11*11+12*12+13*13+14*14)/365
=【1/6*14(14+1)*(14*2+1)-1/6*9*(9+1)*(9*2+1)】/365
=【1/6*14*15*29-1/6*9*10*19】/365
=【1015-285】/365
=730/365
=2

回答2:

(10*10+11*11+12*12+13*13+14*14)/365

=(100+121+144+169+196)/365
=730/365
=2

回答3:

2