Naheal said:
Actually, it didn't :-/ That proof works.
Third last step, at 2a(a-b) = a(a-b). a = b, so dividing by (a-b) is impossible. Yet they still do. So no.
The third last step is still valid, because a-b = 0, so both sides equal 0.
You could just as easily say
532531521215a(a-b) = a(a-b)
532531521215 = 1
which is equally as wrong.
havass said:
If x = 0.999999...
Then 10x = 9.9999...
Therefore, 10x - x = 9
Which implies 9x = 9
Thus, x = 1
x also = 0.99999...
In conclusion, I have just proven 1 = 0.9999...
You're doing it wrong, too. At step 4, 9x = 9, that is not true.
9x = 8.99999999
Edit: I'm not even a math major, but the amount of ignorant false intellectualism in this thread is about to make me cry.