SOLUTION: What are the x's of: (sec)x = (cos)x

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Question 747130: What are the x's of: (sec)x = (cos)x
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
sec%28x%29=1%2Fcos%28x%29 so
sec%28x%29=cos%28x%29 --> 1%2Fcos%28x%29=cos%28x%29 --> %28cos%28x%29%29%5E2=1
A solution that gives cos%28x%29=1 is x=0.
A solution that gives cos%28x%29=-1 is x=180%5Eo (or x=pi radians).
Those are the only solutions such that
0%3C=x%3C360%5Eo (or 0%3C=x%3C2pi if we measure angles in radians).
There is an infinite number of other solutions that can be found by adding/subtracting multiples of 360%5Eo (or 2pi radians).
All solutions can be expressed as
x=k%2A180%5Eo (or x=k%2Apiradians) with k being an integer.