SOLUTION: i ned help using the unit circle. the question is find the exact value of sec (-780 degrees)

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Question 933008: i ned help using the unit circle. the question is find the exact value of sec (-780 degrees)
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
May add multiples of 360 until You get in the positive range
sec(-780) = 1/cos(-780) = 1/cos(-780 + 3(360) = 1/cos(300) =1/(1/2) = 2
sec(-780) = 2
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(cosx, sinx) Summary Unit Circle
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