Answer
The identity is verified.
See the graph of $f(y)=sec~y~cos~y$
![](https://gradesaver.s3.amazonaws.com/uploads/solution/de44e4d5-4161-4f02-a174-4baf79630015/result_image/1564340079.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAJVAXHCSURVZEX5QQ%2F20240727%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240727T013419Z&X-Amz-Expires=900&X-Amz-SignedHeaders=host&X-Amz-Signature=455cd84543fe84a2c8c06b311b3dcc32e1230a79c1200824341043645b06c37d)
Work Step by Step
$sec~y~cos~y=\frac{1}{cos~y}·cos~y=1$
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.