y=sin(2x+π/6)对称轴有四个选项:A:x=-π/12B:x=5π/12C:x=4π/3D:x=π/6

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y=sin(2x+π/6)对称轴有四个选项:A:x=-π/12B:x=5π/12C:x=4π/3D:x=π/6

y=sin(2x+π/6)对称轴有四个选项:A:x=-π/12B:x=5π/12C:x=4π/3D:x=π/6
y=sin(2x+π/6)对称轴
有四个选项:
A:x=-π/12
B:x=5π/12
C:x=4π/3
D:x=π/6

y=sin(2x+π/6)对称轴有四个选项:A:x=-π/12B:x=5π/12C:x=4π/3D:x=π/6
第一步:把2x+π/6当做整体,设t=2x+π/6
第二步;y=sint的对称轴是t=π/2+kπ,则2x+π/6=t=π/2+kπ
第三步:解得x=kπ/2+π/6 即为y=sin(2x+π/6)的对称轴

首先 sinx 的对称轴为kπ+π/2 所以可以
使2x+π/6=kπ+π/2 解得x=kπ/2+π/6 即为y=sin(2x+π/6)的对称轴

x=kπ/2+π/6
sinX对称轴为x=(2k+1)π/2,k为整数
因此令2x+π/6=(2k+1)π/2
得x=(2k+1)π/4-π/12