Heron formula
From HandWiki
A formula expressing the surface area $S$ of a triangle in terms of its sides $a$, $b$ and $c$:
$$S=\sqrt{p(p-a)(p-b)(p-c)},$$
where $p=(a+b+c)/2$. Named after Heron (1st century A.D.).
References
| [a1] | M. Berger, "Geometry", 1–2, Springer (1987) (Translated from French) Template:ZBL |
| [a2] | H.S.M. Coxeter, "Introduction to geometry", Wiley (1961) Template:ZBL |
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