Cách 1: A= (6-2/3+1/2)-(5+5/3-3/2)-(3-7/3+5/2)
A= 35/6-31/6-19/6=35-31-19/6
A= -15/6=-5/2
Cách 2: A= (6-2/3+1/2)-(5+5/3-3/2)-(3-7/3+5/2)
A= 6-2/3+1/2-5+5/3-3/2-3-7/3+5/2
A= (6-3-2)+(2/3-5/3+7/3)+(1/2+3/2-5/2)
A= 1+0-1/2
A= 1/2
A= (6-2/3+1/2)-(5+5/3-3/2)-(3-7/3+5/2)
A= 6-2/3+1/2-5+5/3-3/2-3-7/3+5/2
A= (6-3-2)+(2/3-5/3+7/3)+(1/2+3/2-5/2)
A= 1+0-1/2
A= 1/2