SOLUTION: If we have cos ( theta + (pi/4)) = sqrt(2)/2 and the range is between 0 greater than/or equal to theta less than 2pi. What is theta?

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Question 896201: If we have cos ( theta + (pi/4)) = sqrt(2)/2 and the range is between 0 greater than/or equal to theta less than 2pi. What is theta?
Found 2 solutions by josmiceli, lwsshak3:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+cos+%28+theta+%2Bpi%2F4+%29+=+sqrt%282%29+%2F+2+
+cos+%28+theta+%2Bpi%2F4+%29+=+1+%2F+sqrt%282%29+
Let +alpha+=+theta+%2B+pi%2F4+, then
+cos%28+alpha+%29+=+1%2Fsqrt%282%29+
+alpha+=+pi%2F4+
+alpha+=+%28+5%2Api+%29%2F4+
+alpha+=+theta+%2B+pi%2F4+
------------------------
+pi%2F4+=+theta+%2B+pi%2F4+
+theta+=+0+
------------------------
+%28+5%2Api+%29%2F4+=+theta+%2B+pi%2F4+
+theta+=+pi+
---------------
Those are the 2 solutions for +theta+



Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
If we have cos ( theta + (pi/4)) = sqrt(2)/2 and the range is between 0 greater than/or equal to theta less than 2pi. What is theta?
***
cos%28theta%2Bpi%2F4%29=sqrt%282%29%2F2
%28theta%2Bpi%2F4%29=arccos%28sqrt%282%29%2F2%29
%28theta%2Bpi%2F4%29=pi%2F4
theta=0
and
%28theta%2Bpi%2F4%29=7pi%2F4
theta=3pi%2F2
theta=0, 3π/2