On Friday 29 October 2004 05:23 am, Yohanes Santoso wrote: | Guillaume Marcais <guslist / free.fr> writes: | > x = 0.99999... (infinite serie of 9s) | > 10*x = 9.99999... | > 10*x - x = 9*x = 9 | > So x = 1! | | http://www.math.fau.edu/Richman/html/999.htm | | YS. Nice paper. Thank you. A summary for those who don't have the time: "Clearly 0.9* = 1 + 0¯, so 0¯ is a sort of negative infinitesimal. On the other hand, you can't solve the equation 0.9* + X = 1 because, ..., the sum of a traditional real with any real is a traditional real." Ironically, that's the second time I've read about -0 since I mentioned the all so "obscure" idea the other day. The other was in the lastest IEEE floating point revision --looks like they may support it. Thanks again, T.