函数y=sin(2x+π/3）图象的对称轴方程可能是 A x=-π/6 B x=-π/12 C x=π/6 D x=π/12

题目

函数y=sin(2x+π/3）图象的对称轴方程可能是 A x=-π/6 B x=-π/12 C x=π/6 D x=π/12
能不能在具体点

答案

sin(x)的周期为：T=2π；对称轴为：X=π/2+nπ（n为整数）.
sin(2x)的周期为：T/2=π；对称轴为：X/2=π/4+nπ/2（n为整数）.
sin(2x+π/3)=sin(2(x+π/6))的周期为：T/2=π；对称轴为：X/2-π/6=π/12+nπ/2（n为整数）.
选D.