De fiEVOLCT. DLORIM CORPOBrM, ETC. 451 



Y'.sinw — X.coso 



cos(v — o)=i 

 sin('i;— o)= 



r 

 Y'.coso-t-X. siiiw 



r 



./( 2 //"I, / N ^\^W — /'A'JH-^(Y'.sino — X.coso) 

 y](J' — //A-j-H^ .cos(i' — 0]=-^ — ■ ! — Lj ^ 



r 



sive ob aequalilalem (D') (num. 17). 



/I . ,;,, , V A'^jl/if*'— A/i'i— (X.coso—Y'.sino)! 

 yifi- — /ik-\-i-^ . cos^f— £»)= — -— li ! — 1^_ ii 



(i,r 

 nec non (num. 25, ct 28) 



Y'. cosoH-X.sin o=Y"=/'^±?] J 



.'I* 



X. coso— Y'.sino=X"=[^^") x"' : 

 factis ideo subslitutionibus, erit 



sm.u: 



"A■[^/i^'_AA^Mx"'('f±-")j 



cos.u: 



Hinc 



el 





1 



L= -+-tangM 



\ COSll 



tanf(45°-t-i«)= 



Atque hic, ut m num. 32, quantjtatj ±: I 1 y 



