Lehmus

Lehmus is a surname of German origin. The name appears in historical mathematical literature in connection with a geometric result known as Lehmus’ theorem. In Euclidean geometry, Lehmus’ theorem states that if two internal angle bisectors of a triangle have equal length, then the triangle is isosceles; equivalently, the base angles are equal. The theorem is often presented as a classical problem illustrating geometric reasoning and the relationships between angle bisectors and side lengths.

As a surname, Lehmus has appeared among scholars and scientists in German-speaking regions. Individuals bearing the name have contributed to mathematics and other fields, though specific biographical details vary across sources and may be sparse in the historical record.

In broader use, Lehmus does not denote a contemporary scientific term or concept beyond its role as a surname and its association with the geometry theorem. In discussions of mathematical history, Lehmus’ theorem is cited as an example of how properties of angle bisectors influence triangle symmetry, while the surname itself remains primarily of genealogical and biographical interest.