SOLUTION: Hi, please help me solve this problem: Find the exact value of cot(390 degrees) Thanks!

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Question 402099: Hi, please help me solve this problem:
Find the exact value of cot(390 degrees)
Thanks!
Found 2 solutions by Alan3354, lwsshak3:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
= cot(30)
= sqrt(3)

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Hi, please help me solve this problem:
Find the exact value of cot(390 degrees)
Thanks!
..
The problem here is to determine the reference angle. Using the unit circle to illustrate this, starting from zero deg, rotate counter-clockwise 360 deg or 2pi radians plus an additional 30 deg, which is the reference angle. The cot of that angle, 30 deg, is the adjacent side/opposite side =sqrt(3)