Niels Ryberg Finsen (1860-1904), Danishphysician and 1903 Nobel Prize winner who made important discoveries regarding the use of light waves in the treatment of disease.
... formula reads
<math>
x=\frac{-b \pm \sqrt {b^2-4ac}}{2a}
</math>
The term b2 – 4ac is called the discriminant of the quadratic equation, because ...