$\sec^2 \theta $
Work Step by Step
Re-arrange the given equation as: $=\cos^2 \theta+\sin^2 \theta +\tan^2 \theta$ $=1+\tan^2 \theta$ $=\sec^2 \theta $
You can help us out by revising, improving and updating this answer.Update this answer
After 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.