Question

Daca a*b=2/15 si a*c=11/75 calculati a*(b+c)
b)Daca a*c=7/36 si b*c=19/48 calculati c*(b+a)
c)Daca a=5/6 b+c=7/20 si c-d=1/24 calculati a*b+2*a*c-a*d.

Answer 1

Daca a*b=2/15 si a*c=11/75 calculati a*(b+c)
a*(b+c)=a*b+a*c=2/15+11/75= (10+11)/75=21/75=7/25

b)Daca a*c=7/36 si b*c=19/48 calculati c*(b+a)
c*(b+a)=c*b+c*a=19/48+7/36=(57+28)/144=85/144

c)Daca a=5/6 b+c=7/20 si c-d=1/24 calculati a*b+2*a*c-a*d.
a*b+2*a*c-a*d= a(b+2c-d)=a(b+c+c-d)=5/6(7/20+1/24)=5/6  * (42+5)/120=
=5/6*47/120=47/6*24=47/144