What does R₃ mean in linear algebra?

[abcdefhij]

I am trying to self study linear algebra. This might seem like a very silly question but what does
R subscript 3 mean in the context of linear algebra. I am NOT talking about R ^ 3 which is 3 dimensional vector space

 

[Fredrik]

You may have to provide more information. Where did you see this notation? How was it used?

It could perhaps be the 3rd component of an ordered n-tuple $(R_1,\dots,R_n)$.

 

[homeomorphic]

Means nothing. Whatever source you are reading would have to specify what it meant because it isn't anything standard, as far as I'm aware (usually, even standard things are often defined somewhere, unless they are super-standard, like R^3 is).

 

[homeomorphic]

Actually, I suppose it could mean the 3rd row of a matrix.

 

[HallsofIvy]

Has the author of the particular book or other site you have found this in already used R³ to mean three dimensional real space? If not, although it would not be standard notation, he might be using R₃ to mean that. Otherwise, I agree with Fredrick and homeomorphic. It might be the third component of a vector "R" or the third row of a matrix.