Solve for : .
Answer and explanation
Correct answer: D.
- Step 1: Use the Pythagorean identity to express the equation in terms of : .
- Step 2: Factor the quadratic: . Since , has no real solutions. Thus . On , the solutions in quadrants I and IV are and .
Answer
.
Why not the others: The angles correspond to ; the angles correspond to ; the angles correspond to .
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