I found a torrent online of Apostol's "Mathematical Analysis" 1st edition and I think I found a typo, or whoever scanned the book cut off the edge a bit...(adsbygoogle = window.adsbygoogle || []).push({});

Apostol writes that the extended real number system R* is denoted by [-∞, +∞] while the regular real number system R is denoted by (-∞, ∞). Then he says "The points in R are called 'finite' to distinguish them from the 'infinite' points +∞ and -∞. " Shouldn't it read that the points in R* are finite, not the points in R? Because if you include infinity in the interval, you are treating it as a finite point?

The "R" is the sentence that I quoted above is a the very edge of the page so it could be that the scanner of the book cut off the " * " accidentally, but I just want to confirm...

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# Apostol: infinity as finite point

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