Question 1149260
tan^2(x) - sec(x) - 1 = 0
tan^2 = sec^2 - 1
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sec^2(x) - sec(x) - 2 = 0
(sec - 2)*(sec + 1) = 0
sec = 2, -1
cos = 1/sec
cos(x) = 1/2
x = 60, 300 + n*360 … n = integer
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cos(x) = -1
x = 180 + n*360 … n = integer