g(x)=f(x-φ)=sin(-2(x-φ)+π/3)=sin(-2x+2φ+π/3)当2φ+π/3=π/2时，φ=π/6希望你满意
即sin[-2(x-φ)+π/3]是偶函数则对称轴是x=0即x=0时sin有最值所以sin[-2(0-φ)+π/3]=±1-2(0-φ)+π/3=kπ+π/2φ=π/12
