How do you solve and find the value of #cos^-1(-1)#?

1 Answer
Oct 26, 2016

You can call v its value... Also remember that #cos^-1# is the same as #arccos#...

So, let's say that:

#v=arccos(-1)#

If this is the case, then:

#cos(v)=-1#

It turns out that:

#cos(pi)=-1#

Therefore, #v=pi# and this is your answer. You can check this result by looking at the #y=arccosx# graph below. When #x=-1#, #y=pi# which confirms that the result we've obtained is correct.

graph{y=arccosx [-10, 10, -5, 5]}