The Return of Eric Weisstein's World Of Mathematics
Many readers (like this Anonymous Coward) have written with the good news that "Eric Weisstein's World of Mathematics, a free, online encyclopedia of mathematics was taken off the web thanks to a lawsuit by CRC Publishing. After much legal wrangling, it returns today stronger than ever. See it rise from the ashes at http://mathworld.wolfram.com."
Let x = 1
x^2 - 1 = x - 1
(x-1)(x+1) = (x-1)
divide both sides by (x-1)
x + 1 = 1
2 = 1 !
The middle mind speaks!