Vậy A < B Giải: 12=24:2 (5 2 -1):2 (a + b) 2 = a 2 + 2ab + b 2 (a + b) 2 - 2ab = a 2 + b 2 22 )(a 22 )(b Khai căn sau: 3 1036 −=A 333336 += ( ) 3 3 1.3.3 + 13.310 −−=− ( ) 2 33 − ( ) 3 1 −+ ( ) ( ) ( ) 3 3 2 33 3 11.3.3)1.(3.33 1036 −++−+= −= A ( ) 3 3 13 −= 13 −= A Khai căn sau: 3 1036 −=A 333336 += ( ) 3 3 1.3.3 + 13.310 −−=− ( ) 2 33 − ( ) 3 1 −+ ( ) ( ) 3 32 33 3 11.3.31.3.33 1036 −+−= −= A ( ) 3 3 13 −= 13 −= A