R2 vs. R^2

[DarkLightA]

You know how sometimes it sais R2, while other times it sais

R<sup>2</sup>

? Are they the same?

 

[nitrocan]

I have never seen the second one. It would mean R squared to me.

 

[qqwref]

They are the same. R^2 is a bit older as far as notation goes - it was what people originally used for a half turn, but because it's harder to type or write everyone has gradually started to write R2 for the same thing.

 

[cuBerBruce]

Our notation is based upon Singmaster notation which is really just a specialized use of standard algebraic notation. David Singmaster denoted the basic clockwise 90-degree turns of face layers as U, D, L, R, F, and B. Multiplication can be thought of as meaning "followed by." So UR means "U times R" or "U followed by R". Exponentiation represents repetition, so RR (R followed by R, or R performed twice) can be written as "R²" (R squared). A power of -1 represents an inverse, and is normally simplified to an apostrophe or prime symbol (although that simplification is not a standard convention in mathematics).

Unfortunately, in some ways, the algebraic nature of the notation has been lost somewhat with some of the ways the original Singmaster notation has been extended over the years.