quote:
And, if I'm not mistaken, you're a mathematician.
Heh. A
failed mathematician. But better than some of your teachers, it would seem:
quote:
x=0.999...
10x=9.999...
9x=9
x=1
This is a correct calculation, however the second and third steps do need to be justified. But all this needs to be done using limits; do you remember your calculus? Just nod your head as if you do and we'll proceed.
First, we have to figure out what 0.999999... even means. Here is what it means:
We have a sequence of numbers:
0.9
0.99
0.999
0.9999
...
0.999999... just means the limit of that sequence of numbers. What is the limit? Well, if 1 - 0.999999... = 0, then the limit must be 1. In fact, this is just what it means (the definition) of the limit being equal to 1.
So:
1-0.9=0.1
1-0.99=0.01
1-0.999=0.001
1-0.9999=0.0001
...
Clearly (meaning that it looks obvious and I don't think anyone wants to see an epsilon-delta proof) the limit really is 0.
Hence, 0.999999... = 1.
Does that clear anything up?
-
The whole problem is the idea of infinity. Infinity can get really weird. Look up the
Hotel Infinity when you get the chance. (Cool story, even if it doesn't even get to the weirdness of uncountably infinite!)
Actually, if their god makes better pancakes, I'm totally switching sides. --
Charley the Australopithecine