**Problem : **
What is arccos()?

+2*nΠ*, +2*nΠ*, where

*n* is an integer.

**Problem : **
What is arcsin(0)

*nΠ*, where

*n* is an integer.

**Problem : **
What is arccos()?

There is no solution, because there exists no angle whose cosine

> 1.

**Problem : **
Why aren't the inverse relations functions?

The inverse relations aren't functions because they don't assign a specific
output to each input.

**Problem : **
What are the domains of arcsine, arccosine, and arctangent?

The domains of arcsine and arccosine are

[- 1, 1]. The domain of arctangent is
all real numbers. Note: Although they aren't functions, the term domain can be
used to describe the possible inputs of the relations.