希羅平均數

${\displaystyle H={\frac {1}{3}}\left(A+{\sqrt {AB}}+B\right).}$

${\displaystyle H={\frac {2}{3}}\cdot {\frac {A+B}{2}}+{\frac {1}{3}}\cdot {\sqrt {AB}}.}$

应用

${\displaystyle V={\frac {h}{3}}(B_{1}+B_{2}+{\sqrt {B_{1}B_{2}}})}$

B1是一个底面的面积, B2 是另一个底面的面积。

参考

• Bullen, P.S., Handbook of Means and Their Inequalities, Mathematics and Its Applications 2nd, Berlin, New York: Springer Science+Business Media, 2003, ISBN 978-1-4020-1522-9
• Eves, Howard Whitley, Great Moments in Mathematics (Before 1650), Mathematical Association of America, 1980, ISBN 978-0-88385-310-8