MCQ
The principal value of $\cos ^{-1}\left(-\frac{1}{2}\right)$ is
- A$\frac{\pi}{3}$
- B$\frac{\pi}{6}$
- ✓$\frac{2 \pi}{3}$
- D$\frac{3 \pi}{2}$
✓
Answer
Correct option: C.
$\frac{2 \pi}{3}$
$\frac{2 \pi}{3}$
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