SOLUTION: If cos A = -1/sqrt(2), determine the possible measures of angle A.

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Question 1114122: If cos A = -1/sqrt(2), determine the possible measures of angle A.
Answer by ikleyn(53937) About Me  (Show Source):
You can put this solution on YOUR website!
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cos(A) = -1%2Fsqrt%282%29   ====>


cos(A) = -sqrt%282%29%2F2  ====>


A = 3pi%2F4   or   A = 5pi%2F4.


Answer.  There are two solutions in the interval [0,2pi):  A = 3pi%2F4   or   A = 5pi%2F4.