Geometry

Question Analysis  

The main focus is to determine the coordinates on the unit circle for the angle (135°) using cosine (x-coordinate) and sine (y-coordinate), accounting for its position in the second quadrant.  

 

Key Concept Explanation  

On the unit circle, coordinates for an angle are . For angles in the second quadrant ( < < ), is negative and is positive. is a special angle related to (45°) with reference angle .  

 

Step-by-Step Solution  

1. Identify the reference angle:  

Reference angle for is .  

2. Apply quadrant signs:  

In QII, , .  

3. Use values:  

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