SOLUTION: find two values of theta in degrees (0 greater than or equal to theta< 360 degrees) if cos of theta= - (squareroot of 3)/2, not using a calculator.
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Question 259019: find two values of theta in degrees (0 greater than or equal to theta< 360 degrees) if cos of theta= - (squareroot of 3)/2, not using a calculator. Answer by drk(1908) (Show Source):
You can put this solution on YOUR website! In this problem, you must be familiar with the unit circle or the special triangles 45-45-90; 30-60-90.
cos(theta) = sqrt(3)/2 is a 30 degree angle.
Now since it is negative, it is in quad II or III.
in quad II: 180 - 30 = 150 degrees
in quad III: 180 + 30 = 210 degrees
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