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“The equal internal bisectors theorem, 1840-1940. … Many solutions or none?” A centenary account

Published online by Cambridge University Press:  31 October 2008

James A. M'Bride
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This paper contains (i) a short history of the geometrical theorem proposed in 1840 by Prof. Lehmus of Berlin to Jacob Steiner—“If BJY, CJZ are equal bisectors of the base angles of a triangle ABC, then AB equals AC,” (ii) a selection of some half-dozen solutions from the 50 or 60 that have been given, (iii) some discussion of the logical points raised, and (iv) a list of references to the extensive literature of the subject.

Type
Research Article
Information
Edinburgh Mathematical Notes , Volume 33 , January 1943 , pp. 1 - 13
Copyright
Copyright © Edinburgh Mathematical Society 1943

References

REFERENCES (A Selection)

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