Question

cos^-1\(\left(-\frac{\sqrt{3}}{2}\right)\)

Answer 1

Let cos^-1\(\left(\frac{\sqrt{3}}{2}\right)\) = y
∴ cos y = \(\left(\frac{\sqrt{3}}{2}\right)\) = – cos\(\frac { π }{ 6 }\)
The range of principal value branch is (0, π)
∴ principal value of cos^-1\(\left(\frac{\sqrt{3}}{2}\right)\) is \(\frac { π }{ 6 }\).