Question

若 AB/A+B=1/3 AC/A+C=1/4 BC/B+C=1/5 求ABC/AB+AC+BC等于多少

Answer 1

因为 AB/A+B=1/3 AC/A+C=1/4 BC/B+C=1/5

所以 A+B/AB=3 A+C/AC=4 B+C/BC=5

A+B/AB + A+C/AC + B+C/BC =3+4+5=12

2(AB+AC+BC)/ABC =12

AB+BC+AC/ABC =6

ABC/AB+AC+BC =1/6