ab/(a+b)=1/2
bc/(b+c)=1/3
ac/(a+c)=1/4
所以
(a+b)/ab=1/a+1/b=2
(b+c)/bc=1/c+1/b=3
(a+c)/ac=1/a+1/c=4
右边三式相加
2(1/a+1/b+1/c)=9
1/a+1/b+1/c=9/2
所以,1/c=9/2-2=5/2,1/b=9/2-4=1/2,1/a=9/2-3=3/2
即a=2/3,b=2,c=2/5
ab/(a+b)=1/2
bc/(b+c)=1/3
ac/(a+c)=1/4
所以
(a+b)/ab=1/a+1/b=2
(b+c)/bc=1/c+1/b=3
(a+c)/ac=1/a+1/c=4
右边三式相加
2(1/a+1/b+1/c)=9
1/a+1/b+1/c=9/2
所以,1/c=9/2-2=5/2,1/b=9/2-4=1/2,1/a=9/2-3=3/2
即a=2/3,b=2,c=2/5