If the bisectors of the base angles of a triangle are equal, the triangle is isosceles.
Several solutions of the problem are given in the Gazette for July 1932, and again in the issue of May 1933. It is stated in the former that the problem was mentioned in the Lady’s and Gentleman’s Diary of 1859 and of 1860. The history of the problem is interesting. It appears that it was first proposed in 1840 by Professor Lehmus of Berlin to Jacob Steiner, who had been Professor of Geometry at Berlin since 1834 and held that post until his death in 1863.
Page 365 of note * See also Gesammelte Werke, II, 1882.
Page 368 of note * See also Collected Works, I (ed. Baker, H. F., Cambridge, 1904)Google Scholar.
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