Answer
domain $\{x|x\ne k\pi+\frac{\pi}{2}\}$ (k is an integer), range $\{y|y\le-1\ or\ y\ge1\}$.
Work Step by Step
For $y=sec(x)$, we can find its domain $\{x|x\ne k\pi+\frac{\pi}{2}\}$ (k is an integer), range $\{y|y\le-1\ or\ y\ge1\}$.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.