Is $\cot(x)=\frac{1}{\tan(x)}$? I just found in some place say that $\cot(x)=\frac{1}{\tan(x)}$. 
If you think about it as a function they are definitely not same. but if you think about as a relation between angle in a right angle triangle and its side they will be equal. 
so the question is its right to say they are equal or not( at least pedagogically)?
Update:-
Even wolfram alpha and Desmos say they are not equal ( have different domain).

$$\cot x = \frac {\cos x}{\sin x} = \frac {1}{\frac {\sin x}{\cos x}} = \frac {1}{\tan x}$$
This is true only when $\cot x$ and $\tan x$ are defined.
This equation merely indicates that $\cot x$ and $\frac {1}{\tan x}$ are equal in value (when they are both defined, of course). It does not say that $\cot x$ and $\frac {1}{\tan x}$ are the same function.
