Mathematics

Problem

Find the domain of the function

h(x)=\dfrac{\sec(4x-\pi)}{\tan(2x)}

. a)

\mathbb{R}\setminus\left\{x=\dfrac{\pi}{4}+\dfrac{n\pi}{2},\,x=\dfrac{3\pi}{8}+\dfrac{n\pi}{4},\,n\in\mathbb{Z}\right\}

\mathbb{R}\setminus\left\{x=\dfrac{n\pi}{2},\,x=\dfrac{\pi}{4}+\dfrac{n\pi}{2},\,x=\dfrac{3\pi}{8}+\dfrac{n\pi}{4},\,n\in\mathbb{Z}\right\}

\mathbb{R}\setminus\left\{x=\dfrac{n\pi}{2},\,x=\dfrac{\pi}{4}+\dfrac{n\pi}{2},\,x=\dfrac{\pi}{8}+\dfrac{n\pi}{4},\,n\in\mathbb{Z}\right\}

\mathbb{R}\setminus\left\{x=n\pi,\,x=\dfrac{\pi}{4}+\dfrac{n\pi}{2},\,x=\dfrac{3\pi}{8}+\dfrac{n\pi}{4},\,n\in\mathbb{Z}\right\}