So, in the helicopteron, as the helix is at the same time a sustaining plane, it should be likened to a surface moving horizontally, and in which, consequenty, the resistance to motion will be to the lifting power as thesinus is to the cosinus of the angle formed by such plane with the horizon.
1996, Pentti Zetterberg, Matti Eronen, Markus Lindholm, “Construction of a 7500-Year Tree-Ring Record for Scots Pine (Pinus sylvestris, L.) in Northern Fennoscandia and its Application to Growth Variation and Palaeoclimatic Studies”, in Heinrich Spiecker, Kari Mielikäinen, Michael Köhl, Jens Peter Skovsgaard, editors,Growth Trends in European Forests (European Forest Institute Research Report;No. 5),Springer-Verlag Berlin Heidelberg,→ISBN, page15:
The variations are described in terms of cycles ofsinuses and cosinuses.
2007, Vladimir G. Ivancevic, Tijana T. Ivancevic, “Introduction: Human and Computational Mind”, inComputational Mind: A Complex Dynamics Perspective (Studies in Computational Intelligence;60),Springer-Verlag Berlin Heidelberg,→ISBN,→LCCN, section 1 (Natural Intelligence and Human Mind), pages60–61:
Basically, the rotation of the matrix of the factor loadings L represents its post-multiplication, i.e. L* = LO by the rotation matrix O, which itself resembles one of the matrices included in the classical rotational Lie groupsSO(m) (containing the specificm–fold combination ofsinuses and cosinuses.
(anatomy) a pouch or cavity in a bone or other tissue, especially one in the bones of the face or skull connecting with the nasal cavities (the paranasal sinus)
(pathology) an abnormal cavity or passage such as a fistula, leading from a deep-seated infection and discharging pus to the surface
(trigonometry)sine: in a right triangle, the ratio of the length of the side opposite an angle to the length of the hypotenuse
The mathematical sense “chord of an arc, sine” was introduced in the 12th century byGherardo of Cremona as asemantic loan fromArabicجِيبَ(jība,“chord, sine”) (ultimately a loan fromSanskritज्या(jyā,“bowstring”)) by confusion withجَيْب(jayb,“bosom, fold in a garment”).
Est in sēcessū longō locus: īnsula portum efficit obiectū laterum, quibus omnis ab altō frangitur inquesinūs scindit sēsē unda reductōs.
After long sailing comes land: here an island, its sides jutting round, forms a haven, against which every wave [coming] from the deep sea shatters, and spreads itself into the hollows of thebay.
^De Vaan, Michiel (2008), “sinus”, inEtymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill,→ISBN,page567
“sinus”, inCharlton T. Lewis and Charles Short (1879),A Latin Dictionary, Oxford: Clarendon Press
“sinum”, inCharlton T. Lewis and Charles Short (1879),A Latin Dictionary, Oxford: Clarendon Press
“sinus”, inCharlton T. Lewis (1891),An Elementary Latin Dictionary, New York: Harper & Brothers
"sinus", in Charles du Fresne du Cange,Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
