1/a+1/b>=2倍根号(1/ab) 根号c=根号(1/ab)所以 1/a+1/b>=2倍根号c 1/b+1/c>=2倍根号a 1/c+1/a>=2倍根号b1/a+1/b+1/c>=根号a+根号b+根号c 所以等号成立的条件是 a=b=c又a,b,c为互不相等的正数所以 :(1/a+1/b+1/c)>根号a+根号b+根号c