题目

October 15th is the Global Handwashing Day. Activities are planned in more than 20 countries to get millions of people in the developing world to wash their hands with soap. For example, donators will give 150,000 bars of soap to schools in Ethiopia.Experts say people around the world wash their hands every day, but very few use soap at so-called important moments. These include after using the toilet, after cleaning a baby and before touching food.Global Handwashing Day is the idea of the Public-Private Partnership for Handwashing with Soap. Partners include the United Nations Children’s Fu给出下列四个命题：①若x＞0，且x≠1则lgx+1lgx≥2；②设x，y∈R，命题“若xy=0，则x2+y2=0”的否命题是真命题；③函数y=cos（2x-π3）的一条对称轴是直线x=512π；④若定义在R上的函数y=f（x）是奇函数，则对定义域内的任意x必有f（2x+1）+f（-2x-1）=0．其中，所有正确命题的序号是 ．