8 do dung 100000000000000000000000000000000000000000000000000000000000000000000000%
E=(7+72)+(73+74)+....+(735+736)
E=7(1+7)+73(1+7)+....+735(1+7)
E=7.8+73.8+....+735.8
E=8.(7+73+....+735)
có \(8⋮8\)
\(\Rightarrow8.\left(7+7^3+....+7^{35}\right)⋮8\)
Vậy \(E⋮8\)
hay \(E\div8\)dư 0