Solve the equation for exact solutions over the interval [0, 21). 7 cos²x+14 cos x + 7 = 0 Select the correct choice below and,

Question

Solve the equation for exact solutions over the interval [0, 21).
7 cos²x+14 cos x + 7 = 0
Select the correct choice below and, if necessary, fill in the answer box to
complete your choice.
A. The solution set is
(Type an exact answer, using as needed. Type your answer in
radians. Use integers or fractions for any numbers in the express
Use a comma to separate answers as needed.)
B. The solution is the empty set.

Kunduz · Accepted Answer

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