Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-26T15:27:41.079Z Has data issue: false hasContentIssue false

Acute triangles in the n-ball

Published online by Cambridge University Press:  14 July 2016

Glen Richard Hall*
Affiliation:
University of Minnesota
*
Postal address: School of Mathematics, University of Minnesota Twin Cities, 127 Vincent Hall, 206 Church St. SE, Minneapolis, MN 55455, U.S.A.

Abstract

Using Baddeley's [1] extension of Crofton's differential equation we derive an elementary integral formula for the probability that three randomly chosen points in the unit n-ball in ℝn, with respect to Lebesgue measure, form an acute triangle. When the dimension is 2 this probability is 4/π2 − 1/8, while when the dimension is 3 it is 33/70.

Type
Short Communications
Copyright
Copyright © Applied Probability Trust 1982 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] Baddeley, A. (1977) Integrals on a moving manifold and geometrical probability. Adv. Appl. Prob. 9, 588603.Google Scholar
[2] Baddeley, A. (1977) A fourth note on recent research in geometrical probability. Adv. Appl. Prob. 9, 824860.Google Scholar
[3] Broadbent, S. R. (1980) Simulating the ley hunters. J. R. Statist. Soc. A 143, 109140.Google Scholar
[4] Kendall, D. G. and Kendall, W. S. (1980) Alignment in two-dimensional random point sets. Adv. Appl. Prob. 12, 380424.CrossRefGoogle Scholar
[5] Kendall, M. G. and Moran, P. A. P. (1963) Geometrical Probability. Griffin, London.Google Scholar
[6] Langford, E. (1969) Probability that a random triangle is obtuse. Biometrika 56, 689690.Google Scholar