\(12,49\times12,47=155,7503\)
\(12,48\times12,48=155,7504\)
Vay 12,49.12,47<12,48.12,48
12,49x12,47 và 12,48x12,48
155.7503 < 155,7504
\(\Rightarrow\)12,49x12,47<12,48x12,48
12,49 x 12,47 = 155,7503
12,48 x 12,48 = 155, 7504
Vì 155,7503 < 155 , 7504 nên 12,49 x 12,47 < 12,48 x 12,48
Ta có :
\(12,49\cdot12,47=\left(12,48+0,01\right)\left(12,48-0,01\right)=12,48\cdot12,48-0.0001\)
Mà \(12,48\cdot12,48-0,0001< 12,48\cdot12,48\)
\(\Rightarrow12,49\cdot12,47< 12,48\cdot12,48\)
