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## Homework Statement

Evaluate and express your answer in radians:

$$cot^{-1}\left(1\right)$$

## Homework Equations

## The Attempt at a Solution

I start by identifying that the domain of Arccotangent is all real numbers. So 1 is in the domain.

From here, I looked at the unit circle and saw that ##\frac{π}{4}## has a cotangent of 1, but this was incorrect.

So I pulled out my calculator and evaluated ##\frac{1}{arctan\left(1\right)}##

However, if you'll look at my attached image, the step-by-step instructions say that ##cot\left(x\right)=\frac{1}{tan\left(x\right)}## BUT ##arccot\left(x\right)≠\frac{1}{arctan\left(x\right)}##

Why is this true?

I'm not sure what this page is telling me.