The Gunfight at the O. K. Corral is a legendary event which has been portrayed in numerous Western films. The actual event occurred in a vacant lot near the corral, in Tombstone, Arizona (a corral is like a livery stable[?]; the analogous location in Denver was called the Elephant Corral).
... of characteristic 2, the element 2a is zero and it is impossible to divide by it.)
The symbol
<math>\pm \sqrt {b^2-4ac}</math>
in the formula should be ...