已知三个非零实数a,b,c成等差数列,我们有a+c=2b通分1/a,1/b,1/c可得1/a+1/c=(bc+ab)/abc=（a+c）*b/abc=2b*b/abc1/b+1/b=2ac/abc如果1/a,1/b,1/c是等差数列,那么就有1/b+1/b=1/a+1/c 需要满足2ac/abc=2b*b/abcac=b*b...