Answer
If $x=-2\pi,0,2\pi$, $\sec{x}=1$, if $x=-\pi,\pi$, $\sec{x}=-1$.
Work Step by Step
If $x=-2\pi,0,2\pi$, $\sec{x}=1$, if $x=-\pi,\pi$, $\sec{x}=-1$. (see graph)
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