SOLUTION: For what values of theta,between 0 and 360, does sec of theta equal -2/root 2?

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Question 1073218: For what values of theta,between 0 and 360, does sec of theta equal -2/root 2?
Found 2 solutions by ikleyn, MathTherapy:
Answer by ikleyn(52908) About Me  (Show Source):
You can put this solution on YOUR website!
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It is the same value of theta, for which cos%28theta%29 = -sqrt%282%29%2F2, i.e. theta = 3pi%2F4 (135 degs) or theta = 5pi%2F4 (225 degs).


The tutor "MathTherapy" missed one solution.


Answer by MathTherapy(10557) About Me  (Show Source):
You can put this solution on YOUR website!
For what values of theta,between 0 and 360, does sec of theta equal -2/root 2?
Since sec is negative (< 0), cos is also negative (< 0).

Hence, theta is in the 2nd and 3rd quadrants, and has values of: highlight_green%28matrix%281%2C3%2C+135%5Eo%2C+and%2C+225%5Eo%29%29

Ikleyn(11508) is correct. I did miss one of the values: the one in the 2nd quadrant.