Son of Acheron and Orphne. He told the other gods that Persephone had eaten a pomegranate in Hades. He was punished by being changed into an owl. (Ovid V, 534)
... symbol
<math>\pm \sqrt {b^2-4ac}</math>
in the formula should be understood as "either of those element(s) of the field whose square equals b2 - 4ac". ...