Land's End is a peninsula located at the extreme western tip of Cornwall, Great Britain near Penzance[?]. Visible from Land's End is the Longships Lighthouse. The Longships, a few miles out, is a serpentine and quartz island. Offshore, midway between Land's End and the Scilly Isles, lies the mythical lost land of Lyonesse, referred to in Arthurian literature.
... Generalizations
The formula and its proof remain correct if the coefficients a, b and c are complex numbers, or more generally members of any field whose ...