Given that and , find the exact value of the acute angle .

Answer and explanation

Correct answer: D.

  1. Step 1: Use the tangent addition formula: .
  2. Step 2: Substitute and : . Since and are acute with positive tangents, .
Answer
.
Why not the others: The value corresponds to ; the value corresponds to ; the value represents an undefined tangent where the denominator vanishes.

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