Which is equivalent to [tex]\cos^{-1}(0)[/tex]? Give your answer in radians.

A. 0
B. [tex]\frac{\pi}{2}[/tex]
C. [tex]\pi[/tex]
D. [tex]2\pi[/tex]



Answer :

To determine the value of [tex]\(\cos^{-1}(0)\)[/tex], we first need to understand that [tex]\(\cos^{-1}(x)\)[/tex] (also known as [tex]\(\arccos(x)\)[/tex]) represents the angle [tex]\(\theta\)[/tex] such that [tex]\(\cos(\theta) = x\)[/tex].

We are asked to find [tex]\(\cos^{-1}(0)\)[/tex]. This means we need to identify the angle [tex]\(\theta\)[/tex] for which
[tex]\[ \cos(\theta) = 0. \][/tex]

The cosine function equals 0 at specific points within its range. The most common angles where the cosine function equals 0 are [tex]\(\frac{\pi}{2}\)[/tex] and [tex]\(\frac{3\pi}{2}\)[/tex]. However, the principal value of [tex]\(\cos^{-1}(x)\)[/tex] is typically taken within the range [tex]\([0, \pi]\)[/tex].

In this range, the angle [tex]\(\theta\)[/tex] where [tex]\(\cos(\theta) = 0\)[/tex] is
[tex]\[ \theta = \frac{\pi}{2}. \][/tex]

Thus, the value of [tex]\(\cos^{-1}(0)\)[/tex] is [tex]\(\frac{\pi}{2}\)[/tex] radians. Therefore, the correct answer is:
[tex]\[ \boxed{\frac{\pi}{2}} \][/tex]