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# Title: [Johannis Wallis S. T. D. Geometriae Professoris Saviliani, in Celeberrima Academia Oxoniensi, De Algebra Tractatus; Historicus & Practicus. Anno 1685 Anglice editus; Nunc Auctus Latine. Cum variis Appendicibus; Partim prius editis Anglice, Partim nunc primum editis] Johannis Wallis S. T. D. Geometriæ Professoris Saviliani, in Celeberrima Academia Oxoniensi, De Algebra Tractatus; Historicus & Practicus. Anno 1685 Anglice editus; Nunc Auctus Latine. Cum variis Appendicibus; Partim prius editis Anglice, Partim nunc primum editis (shelfmarks Leibn. Marg. 100:1/2, Stück 2; Leibn. Marg. 100:1/2)
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PRTGONOMETETA SPHERICA.
20. Pex RCG. 6. S ZCr. SZer:: rZ P. FZZLL, VerE.
Ergo terminos ho.
RCg. 7. 73ZOr. YZZOr:: TZZLL BaC. FZZ LLbaI. Emolosos invicem
RC9. 8. TZXLLbaC. YZXLL. Vert. :: r= P. TEZLLbaT.) mulciplicando.
S, Zer X TZZer. S, XOr XYZXOr:: 79ZP. TG ZZLL baL. ErgO (per Jem. 2.)
2.92Zer. Z.9: Xor:: 7q= P. I93 DLLbaC. ErBO Z ZZCr. Z.ZXOr:: 7ZP. TZZLL. bal.
Demonstracio ilta lupponit P =Z LL Vert. 1. c. perpendicularem cadere intra
Friangulum: Sed et exdem proportiones oriuntur, li Cadat extra.
PRDBF F M A
In Triangulo quovis Sphaerico datis 2 angulis et bale incerjecta invenire latera
reliqua, vel anguli tertii crura.
S3 Z LL.SZX Luta:: T Zba(. FZ XCr.
2 32 L6. Z.3X Lab:: TXDaL. T 3Z OY.
Demonstratio nicitur iisdem Lemmaribus _ Regulis quibus praecedens. Sed et
Patimi ex praecedenre constei, si muretur criangulum ulcimum in sibi supplemen.
rale.
RF GV F A IZ.
In Triansulo quoris Sphaerico demisso a vertice arcu perpendiculari ad ba-
Tem: eric.
FF7 segmentorum batis. TZZer:: T Z Xor. T Z X segm. BaI. Nam Per RCS. 2.
ZyBP. Z,DP:: Z BA. Z,DA. ErgO Z BP F ZgDP. ZBP ∞ ZGOP:: Z BA F ZyDA.
Z, BA ∞ Z, DA. FYSO (Per Tem. 7.) =2Zer. TZXCr:: rZT Ccom. TZ Z legm
Frgo FEXer. T Z X Ccgm.:: (7 = 2er. 7ZL. SCgm. . :) F2Z Teom. YZLBr.
P ROBL F. M A.
Daris Frianguli Sphaeriei3 Lateribus, invenire angulum. Demittatur per-
pendicularis, exieque T= bal. Y LZer:: T= Xor. F, F. Tum F F 3 bal. = sCB.
mento majori. e si F = ba C. perpendicularis cadir exta Friangulum.
minori
Tum
R. 2, BP:: T, BA. Z B
e R. T, DP:: Z, D A. Z, D
intra