Question 1182118
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If sec(x) = -0.5, then cos(x) = -2 if we apply the reciprocal to both sides. Recall that sec = 1/cos.


Also, recall that the range for cosine is {{{-1 <= cos(x) <= 1}}}. Meaning that cos(x) between -1 and 1 inclusive of both endpoints. The value -2 is outside this interval, so it's impossible to have cos(x) = -2 where x is a real number. 
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