$x=\pi +2n\pi$ where $n$ is any integer

$x=2n\pi ,\pi +2n\pi$ where $n$ is any integer

$x=2n\pi$ where $n$ is any integer

$x=\frac{\pi }{2}+2n\pi ,\frac{3\pi }{2}+2n\pi$ where $n$ is any integer