Answer
See below.
Work Step by Step
If we have an equation containing a sine and cosine, sometimes we have to square both sides in order to use the Pythagorean identity. But it is important to check for extraneous solutions.
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.