Find the value of x if $x = \dfrac{1 + \tan^2 \phi}{\tan \phi \, \csc^2 \phi}$.

$\begin{align}
x & = \dfrac{1 + \tan^2 \phi}{\tan \phi \, \csc^2 \phi} \\
\\
& = \dfrac{\sec^2 \phi}{\tan \phi \, \csc^2 \phi} \\
\\
& = \dfrac{\dfrac{1}{\cos^2 \phi}}{\dfrac{\sin \phi}{\cos \phi} \cdot \dfrac{1}{ \, \sin^2 \phi}} \\
\\
& = \dfrac{\dfrac{1}{\cos^2 \phi}}{\dfrac{1}{\sin \phi \, \cos \phi}} \\
\\
& = \dfrac{\dfrac{1}{\cos \phi}}{\dfrac{1}{\sin \phi}} \\
\\
& = \dfrac{\sin \phi}{\cos \phi} \\
\\
& = \tan \phi
\end{align}$