E561 -- Variae observationes circa angulos in progressione geometrica progredientes
(Various observations about angles proceeding in geometric progression)
From sin(2f) =
cos f, he gets the infinite product
sin f =
cos(f/16).... He reciprocates, and by
logarithmic differentiation, gets an infinite sum for 1/f
involving cotangents and tangents.
According to the records, it was presented to the St.
Petersburg Academy on November 15, 1773.
Originally published in Opuscula Analytica 1, 1783, pp. 345-352
Opera Omnia: Series 1, Volume 15, pp. 498 - 508
- Original Publication: E561
- An English translation of this article has been done by Jordan Bell: E561.
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