Sagot :
A=7/1*1/3-1/3. B=7/4-3*3/4*5.
=7*1/1*3-1/3. =7/4-9/20
=7/3-1/3. =7*5/4*5-9/20
=6/3. =35/20-9/20
=2/1. =24/20
=7*1/1*3-1/3. =7/4-9/20
=7/3-1/3. =7*5/4*5-9/20
=6/3. =35/20-9/20
=2/1. =24/20