Question:
If the complex number (1 + 2i cosθ) / (1 - 3i cosθ) is purely imaginary, then find the number of values of θ in the interval [-2π, 2π].
If the complex number (1 + 2i cosθ) / (1 - 3i cosθ) is purely imaginary, then find the number of values of θ in the interval [-2π, 2π].
Updated On: Feb 5, 2026
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Correct Answer: 8
Solution and Explanation
The Correct answer is 8.
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