Question

Tính ( hợp lí nếu có thể )

2005 . 2005 - 2004 . 2006

Answer 1

2005.2005-2004.2006

=(2004+1).2005-2004.2006

=2004.2005+2005-2004.2006

=(2004.2005+2004)+1-2004.2006

=2004.(2005+1)+1-2004.2006

=2004.2006+1-2004.2006=1

Answer 2

Ta có:2005*2005-2004*2006=2005*2005-2004*(2005+1)=2005*2005-2004*2005+2004=(2005*2005-2004*2005)+2004

=(2005*(2005-2004))+2004=2005*1+2004=2005+2004=4009

Answer 3

2005 . 2005 - 2004 . ( 2005 + 1)

2005 . 2005 - ( 2004 + 1 ) . 2005

2005 . 2005 - 2005 . 2005 

 = 0

Answer 4

chắc mình làm sai rồi bạn ơi !

Answer 5

2005 . 2005 - 2004 . 2006

= 2005 . 2005 - (2005 - 1) . 2006

= 2005 . 2005 - 2005 . 2006 - 2006

= (2005 . 2005 - 2005 . 2006) - 2006

= 2005 . (2005 - 2006) - 2006

= 2005 . (-1) - 2006

= - 2005 -2006

= -4011