So sánh: A = 2013.2015 B = 2014.2014
Giải thích
A = 2013.2015
= 2013 × (2014 + 1)
= 2013 × 2014 + 2013 × 1
= 2013 × 2014 + 2013 (1)
B = 2014.2014
= 2014 × (2013 + 1)
= 2014 × 2013 + 2014 × 1
= 2014 × 2013 + 2014 (2)
Từ (1), (2) ta có: A < B.
A = 2013.2015
= 2013 × (2014 + 1)
= 2013 × 2014 + 2013 × 1
= 2013 × 2014 + 2013 (1)
B = 2014.2014
= 2014 × (2013 + 1)
= 2014 × 2013 + 2014 × 1
= 2014 × 2013 + 2014 (2)
Từ (1), (2) ta có: A < B.