Question 1141649
Solve for x:   3 + cos 2x = 7/2; only include answers on [0, 2π]
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3 + cos(2x) = 7/2
cos(2x) = 1/2
2x = pi/3, 5pi/3, 7pi/3, 11pi/3
x = pi/6, 5pi/6, 7pi/6, 11pi/6