20092009*200820082008-200920092009*20082008
=2009*10001*2008*100010001-2009*100010001*2008*10001
=0
\(20092009\times200820082008-200920092009\times20082008\)
\(\Rightarrow2009\times10001\times2008\times100010001-2009\times100010001\times2008\times10001\)
\(\Rightarrow0\)
Ủng hộ nha