Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-14T08:14:18.628Z Has data issue: false hasContentIssue false

Alice’s adventures in inverse tan land – mathematical argument, language and proof

Published online by Cambridge University Press:  21 October 2019

Paul Glaister*
Affiliation:
Department of Mathematics, University of Reading, Reading e-mail: p.glaister@reading.ac.uk

Extract

Andrew Palfreyman’s article [1] reminds us of the result (1)

$${\rm{ta}}{{\rm{n}}^{{\rm{ - 1}}}}{\rm{ + ta}}{{\rm{n}}^{{\rm{ - 1}}}}\,2{\rm{ + ta}}{{\rm{n}}^{{\rm{ - 1}}}}{\rm{ 3 = }}\,\pi {\rm{, }}$$
having been set the challenge of finding the value of the left-hand side by his head of department at the start of a departmental meeting.

Type
Articles
Copyright
© Mathematical Association 2019 

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

Palfreyman, A., Inverse tan does it add up to anything?, Mathematics in School, 47(1) (2018) pp. 24-25.Google Scholar
Abeles, F. F., Charles, L. Dodgson’s geometric approach to arctangent relations for pi, Historia Mathematica, 20 (1993) pp. 151-159, also available at http://users.uoa.gr/~apgiannop/Sources/Dodgson-pi.pdf 10.1006/hmat.1993.1013CrossRefGoogle Scholar
Department for Education, GCE AS and A level subject content for mathematics (2014) also available at https://www.gov.uk/government/publications/gce-as-and-a-level-mathematicsGoogle Scholar