# Meaning of mathematic operator

1. Oct 20, 2011

### songoku

1. The problem statement, all variables and given/known data
What is the difference between ≤ (less than or equal to) and "less than over equal to" (the operator is similar but there are 2 lines under the 'less than' operator)

2. Relevant equations
none

3. The attempt at a solution
I simply do not know the difference. And how to use the operator "less than over equal to" ?

Thanks

2. Oct 20, 2011

### Ray Vickson

They mean the same thing; they are just two slightly different notations for the same concept.

RGV

Last edited: Oct 20, 2011
3. Oct 20, 2011

### songoku

If they mean the same thing (I mean 100% same, no difference at all), why are there two notations?

Maybe this will help me more:
1. Is x ≤ 3 the same as x less than over equal to 3 ?

2. Are there any cases we must use "less than over equal to", not ≤ ?

Thanks RGV

4. Oct 20, 2011

### eumyang

Last edited by a moderator: Apr 26, 2017
5. Oct 20, 2011

### songoku

I don't really understand that vector inequalities. I think it means that in vector inequalities, if x ≤ y, it means that x ≠ y.

Maybe you want to tell me that one of the application of "less than over equal to" is in vector inequalities.

Thanks

Last edited by a moderator: Apr 26, 2017