To be completely honest, this looks like what I like to refer to as “symbol vomit”. And also, the square root of 0 is just 0, that is the definition you will find almost everywhere, so there is no need for this weird symbol salad. As for the author, I couldn’t find him apart from like two of his books, do you have any more infos on him? Because this looks very non-mathematical apart from the symols.
To be completely honest, this looks like what I like to refer to as “symbol vomit”. And also, the square root of 0 is just 0, that is the definition you will find almost everywhere, so there is no need for this weird symbol salad. As for the author, I couldn’t find him apart from like two of his books, do you have any more infos on him? Because this looks very non-mathematical apart from the symols.