Albert Girard

Girard, Albert 

Born 1595 in Saint-Mihiel; died 1632 in The Hague. Dutch mathematician. Student of S. Stevin.

Girard was the first to state the fundamental theorem of algebra; he also examined negative and imaginary roots of equations on a par with positive roots. In his Treatise on Trigonometry (1626) he systematized all the theorems of plane and spherical trigonometry known up to that time.

REFERENCES

Wileitner, H.lstoriia matematiki ot Dekarta do serediny 19 stoletiia, 2nd ed. Moscow, 1966. (Translated from German.)