Answer
0
Work Step by Step
1. Distribute
$\cot(180^{\circ}n+90^{\circ})$
2. If n is an integer, then all possible angles are coterminal with either 90 or 270 degree angles. Therefore, the answer is:
$\cot 90^{\circ}=\ cot 270^{\circ}= 0$
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.