Answer to Question #87410 in Trigonometry for Rena

Question

The range of y=Arccos x is (-pi/2, pi/2). True or False? http://prntscr.com/n65cit

Answer 1

Answer: No

Explanation:

$y = \arccos(x)$, by definition $x \in [-1, 1]$

example (show why that range is not correct): $\arccos(-1) = \pi \notin (-\frac{\pi}{2},\frac{\pi}{2})$

the correct range is $[0, \pi]$: $\cos(y) = x \in [-1, 1]$