推荐解答

证明:

∵a+b+c=1

∴1/a+1/b+1/c=(a+b+c)/a+(a+b+c)/b+(a+b+c)/c

=1+b/a+c/a+a/b+1+c/b+a/c+b/c+1

=(b/a+a/b)+(c/a+a/c)+(b/c+c/b)+3

≥2+2+2+3=9

∴1/a+1/b+1/c≥9