Edward de Vere (April 22, 1550 - 1604) was the 17th Earl of Oxford. Some people have theorized that he was actually the author of William Shakespeare's plays.
... we get
<math>x=\frac{-b}{2a}\pm\frac{\sqrt{b^2-4ac}}{2a}=\frac{-b\pm\sqrt{b^2-4ac}}{2a}.</math>
Generalizations
The formula and its proof remain ...