Quote:
Originally Posted by jhawkkw
.99999... does in fact equal 1 and can be easily mathematically proved.
Let x=.9999999......
Therefore 10x=9.99999.......
10xx =9x. == 9.99999......999999....=9
So 9x=9
9x÷9 = 9÷9
Therefore x=1 which was equal to .999999... originally.

don't let students know that
(some profs say that 69.999 doesn't equal 70, lol)