第一题：【By 西陵楚客】由柯西不等式(a+b+c)(1/a+1/b+1/c)>=(a*1/a+b*1/b+c*1/c)^2=(1+1+1)^2=9a+b+c=1所以1/a+1/b+1/c>=9又由柯西不等式[(a+1/a)^2+(b+1/b)^2+(c+1/c)^2](1+1+1)>=[(a+1/a)*1+(b+1/b)*1+(c+1/c)]^2...