Geometry

Question Analysis  

The task is to find the unit circle coordinates for  (135°) by relating it to Quadrant I’s 45° () ratio and adjusting signs for Quadrant II using reference angles.  

 

Key Concept Explanation  

Reference Angle:  lies in Quadrant II. Its reference angle is  (45°).  

Trig Signs in QII: Cosine (x) is negative, sine (y) is positive (ASTC: Sin (+) in QII).  

 

Step-by-Step Solution  

1. Identify the reference angle:  

Reference angle =  (45°).  

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3. Adjust signs for Quadrant II:  

,  

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