已知a>0,b>0,c>0.且a+b+c=3.求
1/(a+b)+1/(b+c)+1/(c+a)的最小值
解:由柯西不等式可知
(a+b+b+c+c+a)x[1/(a+b)+1/(b+c)+1/(c+a)]>=9
2(a+b+c)x[1/(a+b)+1/(b+c)+1/(c+a)]>=9
1/(a+b)+1/(b+c)+1/(c+a)>=9/6=3/2
已知a>0,b>0,c>0.且a+b+c=3.求
1/(a+b)+1/(b+c)+1/(c+a)的最小值
解:由柯西不等式可知
(a+b+b+c+c+a)x[1/(a+b)+1/(b+c)+1/(c+a)]>=9
2(a+b+c)x[1/(a+b)+1/(b+c)+1/(c+a)]>=9
1/(a+b)+1/(b+c)+1/(c+a)>=9/6=3/2