I suppose you might be right for some people. For me, the fact that repeating infinite decimal expansions are rational is deeply deeply ingrained. Since your post is essentially how to square your feelings with what turns out to be mathematically true, you have a lot of room for disagreement as there is no contradiction in different people feeling different ways about the same facts.
For me the most fun thing about 0.9999.… is that 1⁄9 = .11111… and therefore 9x1/9 = 9x.111111..… and this last expression obviously = .99999...
You should also do a search on “right” in your post and edit it, you use “right” one time where you really need “write” I think it is “right down” instead of “write down” but I’ll let you do the looking.
Fixed the typo. Also changed the argument there entirely: I think that the easy reason to assume we’re talking about real numbers instead of rationals is just that that’s the default when doing math, not because 0.999… looks like a real number due to the decimal representation. Skips the problem entirely.
I suppose you might be right for some people. For me, the fact that repeating infinite decimal expansions are rational is deeply deeply ingrained. Since your post is essentially how to square your feelings with what turns out to be mathematically true, you have a lot of room for disagreement as there is no contradiction in different people feeling different ways about the same facts.
For me the most fun thing about 0.9999.… is that 1⁄9 = .11111… and therefore 9x1/9 = 9x.111111..… and this last expression obviously = .99999...
You should also do a search on “right” in your post and edit it, you use “right” one time where you really need “write” I think it is “right down” instead of “write down” but I’ll let you do the looking.
Fixed the typo. Also changed the argument there entirely: I think that the easy reason to assume we’re talking about real numbers instead of rationals is just that that’s the default when doing math, not because 0.999… looks like a real number due to the decimal representation. Skips the problem entirely.