Question 517825
using a calculator o approximate two values of theta in radians when (theta is greater than  or equal to zero and less than 2 pie) 
if sec theta = -2
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Comment: Way to think about the problem.
If sec(theta) = -2, cos(theta) = -1/2
If cos(theta) were 1/2, theta would be pi/3
But cos(theta) is -1/2, so theta is pi +-  (pi/3) = (2/3)pi or (4/3)pi
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invcos(-1/2) = (2/3)pi or (4/3)pi
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Cheers,
Stan H.
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