Sagot :
k=5/7-14/25*15/49=5/7-(2*7/5*5)*(3*5/7*7)=5/7-(2/5*3/7)=5/7-6/35=25/35-6/35=19/35
K = 5/7 - 14/25 x 15/49
=5/7-2/5x3/7
=5/7-6/15
=75/105-42/105
=33/105
=11/35
=5/7-2/5x3/7
=5/7-6/15
=75/105-42/105
=33/105
=11/35