Difference between ≡ and = in math notation

[Sisyphus]

$$V_{x} \equiv \Delta x / \Delta t$$


What is the difference between $$\equiv$$ and = ?

I know that it means congruency in math but I somehow doubt that it's the case in this situation :P

 

[Arkronus]

there's no difference, it just means average velocity is equal to change of distance divided by change of time.

 

[Sisyphus]

i figured as much...

is there a reason for this convention? (the textbook uses both throughout)

 

[Arkronus]

not sure, maybe the extra line on the equal sign just means that it's not just a number answer but also with units.

 

[Sisyphus]

I see

well, thanks for the quick response!

 

[Integral]

It is usually used to denote a definition. So your statement is a definition of V_x

 

[FrogPad]

Check both these links, they are quick reads.


http://mathworld.wolfram.com/Equivalent.html
http://mathworld.wolfram.com/Defined.html