Question

Consideram numerele rationale a,b si c.Se stie ca a*b=$2 \frac{3}{7} si  a * c= - \frac{3}{14}$
a.Calculati a*(b+c) si a *(b-c)
b.Daca b+c=$\frac{31}{7}$,calculati a.

Answer 1

ab=2intregi3/7
ab=(2x7+3)/7
ab=17/7
ac=-3/14
a) a(b+c)=ab+ac=17/7-3/14=(17x2-3)/14=(34-3)/14=31/14=2,2(142857)

a(b-c)=ab-ac=17/7-(-3/14)=17/7+3/14=(17x2+3)/14=37/14=2,6(428571)