A  ( 10  2) 3  5 = ( 5 1) 6 2 5   = ( 5 1) ( 5 1)  2 = ( 5 1)(...

Bài 2:

A  ( 10  2) 3  5

=

( 5 1) 6 2 5  

= ( 5 1) ( 5 1) 

2

=

( 5 1)( 5 1)  

= 4