Leonhard Euler · 1748 · Internet Archive
Introductio in analysin infinitorum
All 320 leaves · leaf 226
Transcription
LIB. I.
198
DE MULTIPLICATIONE
CAPUT XIV.
De multiplicatione ac divisione Angulorum.
234. Sit Angulus, vel Arcus, in Circulo cujus Radius $= 1$, quicunque $= z$; ejus Sinus $= x$; Cosinus $= y$, & Tangens $= t$; erit $xx + yy = 1$ & $t = \frac{x}{y}$. Cum igitur, uti supra vidimus; tam Sinus quam Cosinus Angulorum $z; 2z; 3z; 4z; 5z; \&c.$, constituant Seriem recurrentem cujus scala relationis est $2y, -1$; primum Sinus horum Arcuum ita se habebunt:
$sin. 0z = 0$
$sin. 1z = x$
$sin. 2z = 2xy$
$sin. 3z = 4xy^2 - x$
$sin. 4z = 8xy^3 - 4xy$
$sin. 5z = 16xy^4 - 12xy^2 + x$
$sin. 6z = 32xy^5 - 32xy^3 + 6xy$
$sin. 7z = 64xy^6 - 80xy^4 + 24xy^2 - x$
[TRUNCATED]
This text was produced by machine and has not been corrected by hand. Where it matters, read the scan. Confidence is the model's own, not an external check.