Originally Posted by Buyimports2
The point of the argument is saying that .9999 repeating = 1 is NOT rounding. It's saying that it is a property of infinity. And no, my mom = an elephant is not all the proof that is needed.
I'm still trying to wrap my head around this one, but I would just say that at a cursory glance, this is a problem of infinite limits, and algebra does not typically deal well with infinite limits.
The correct way to prove this one way or the other is to create an expression for 0.9999..... with respect to a variable and take the limit using calculus of that variable as it approaches infinity.