Question

Principal Solution of $ (5 \sin \theta)(2 \cos \theta + 1) = 0 $

• A. \( \frac{2\pi}{3} \), \( \frac{4\pi}{3} \)
• B. \( \frac{2\pi}{3} \), \( \frac{1}{3} \), \( \frac{2\pi}{3} \)
• C. \( \frac{3\pi}{3} \), \( \frac{1}{3} \), \( \frac{2\pi}{3} \)
• D. \( \frac{5\pi}{3} \), \( \frac{1}{3} \), \( \frac{2\pi}{3} \)

Hint:

When solving trigonometric equations, remember to break the equation into factors. Find the solutions for each factor individually.