f(x+a)=f(x-a)恒成立,则x=a为函数f(x)=sin(2x+π/6)的图象的对称轴,
所以,sin(2a+π/6)=1或 -1,得2a+π/6=kπ+π/2,即a=kπ/2+π/6,k为整数,
由a∈(0,π),得a=π/6或2π/3.