观察函数y=sin(2x+5π/2)的图像知,其对称轴必垂直x轴且经过函数最高点或函数最低点而-1≤sin(2x+5π/2)≤1所以令sin(2x+5π/2)=1,得:2x+5π/2=2kπ+π/2,(k∈z);x=kπ-π,(k∈z)又令sin(2x+5π/2)=-1,得:2x+5π/2=2kπ+3π/2,(k∈z);x=kπ-π/2,(k∈z)所以所求对称轴方程是x=kπ/2,(k∈z)
