SOLUTION: What is the reference of 5pi divided by 4? I cannot seem to figure it out.

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Question 286551: What is the reference of 5pi divided by 4? I cannot seem to figure it out.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Since pi%3C5pi%2F4%3C3pi%2F2, this means that 5pi%2F4 is in the 3rd quadrant. If you draw out the angle along with its associated triangle, you'll see that the reference angle is the angle that is closest to the origin. Since pi is the closest known angle, and 5pi%2F4%3Epi, we know that we have to subtract pi from this angle to find the reference angle.


So 5pi%2F4-pi=5pi%2F4-4pi%2F4=%285pi-4pi%29%2F4=pi%2F4 which means that the reference angle is pi%2F4