关于原点对称
π/6-2x=kπ
2x-π/6=-kπ
2x=-kπ+π/6
x=-kπ/2+π/12(k为一切整数)
关于Y轴对称
π/6-2x=kπ+π/2
2x-π/6=-kπ-π/2
2x=-kπ-π/3
x=-kπ/2-π/6 (k为一切整数)