证明不等式 [2a]+[2b]>=[a]+[a+b]+[b]
问题描述:
证明不等式 [2a]+[2b]>=[a]+[a+b]+[b]
不是[a]+[b]
答
记m=[a]、n=[b]、p=a-[a]、q=b-[b]
则[2a]+[2b]=2m+2n+[2p]+[2q]
[a]+[a+b]+[b]=2m+2n+[p+q]
易知0≤p