SOLUTION: Find all t in the interval [0, 2π] satisfying (cos t)2 + 4 cos t + 3 = 0.

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Question 673022: Find all t in the interval [0, 2π] satisfying (cos t)2 + 4 cos t + 3 = 0.



Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Find all t in the interval [0, 2π] satisfying (cos t)2 + 4 cos t + 3 = 0.
cos ^2 t+4cos t+3=0
(cos t+3)(cos t+1)=0
cos t+3=0
cos t=-3 (reject, (-1 ≤ cos t ≤1)
(cos t+1)=0
cos t=-1
t=π