Ta có : 22008 + 22009 + 22010
= 22008.(1 + 2 + 22)
= 22008.(1 + 2 + 4)
= 22008.7 \(⋮\)7
\(\Rightarrow\)22008 + 22009 + 22010 \(⋮\)10 (đpcm)
\(2^{2008}+2^{2009}+2^{2010}\)
\(=2^{2008}\left(1+2+2^2\right)\)
\(=2^{2008}.7⋮7\)
\(\Rightarrowđpcm\)
\(2^{2008}+2^{2009}+2^{2010}\)
\(=2^{2008}\left(1+2+2^2\right).\)
\(2^{2008}.7⋮7\)(vì 7 chia hết cho 7)
Vậy \(2^{2008}+2^{2009}+2^{2010}⋮7\left(đpcm\right)\)
Ta có:
22008 + 22009 + 22010 = 22008 (1 + 2 + 22) = 22008 . 7 chia hết cho 7