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Cosine equals 1/2 at which two angles in one full turn?
Aπ/6 and 5π/6
B2π/3 and 4π/3
Cπ/3 and 2π/3
Dπ/3 and 5π/3
Answer & Solution
Correct answer: D. π/3 and 5π/3
Cosine is positive in the first and fourth quadrants, giving π/3 and 2π − π/3 = 5π/3.
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