Geometry

Question Analysis  

The main focus is to use the Pythagorean identity to find when and is in Quadrant II, where is positive.  

 

Key Concept Explanation  

Pythagorean identity: relates sine and cosine.  

Quadrant signs: In QII, > 0 (positive) and < 0 (negative).  

 

Step-by-Step Solution  

1. Substitute into the identity:  

 

2. Solve for

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