函数y=2sin(2x+α)(-π

题目

函数y=2sin(2x+α)(-π<α<0)图像的一条对称轴是直线x=π/8,求α

答案

∵y=2sin(2x+α)的一条对称轴是直线x=π/8
∴①2sin(2*π/8+α)=2
2sin(π/4+α)=2
∴π/4+α=π/2+2kπ
α=π/4+2kπ
∵-π