SOLUTION: Find the smallest number θ larger than 11π such that cos θ = -1/2. Give exact answer

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Question 822507: Find the smallest number θ larger than 11π such that cos θ = -1/2.
Give exact answer
Answer by lwsshak3(11628) About Me  (Show Source):
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Find the smallest number θ larger than 11π such that cos θ = -1/2.
Give exact answer.
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arccos(-1/2)=2π/3+2πn,n=integer
2π/3+2πn>11π
2+6n>33
6n>31
n>31/6=5+
n=6
..

smallest number θ larger than 11π = 38π/3