Demonstration.
Make(α) 1.1 OA or OF (N. 2.) as before = a, AF=b, and FI now = x; then will OI=a−x and having drawn the Arch FK at the Interval AF, so that AK may be equal to this, and FI=
Mathesis enucleata, or, The elements of the mathematicks by J. Christ. Sturmius ; made English by J.R. and R.S.S.
About this Item
- Title
- Mathesis enucleata, or, The elements of the mathematicks by J. Christ. Sturmius ; made English by J.R. and R.S.S.
- Author
- Sturm, Johann Christophorus, 1635-1703.
- Publication
- London :: Printed for Robert Knaplock and Dan. Midwinter and Tho. Leigh,
- 1700.
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To the extent possible under law, the Text Creation Partnership has waived all copyright and related or neighboring rights to this keyboarded and encoded edition of the work described above, according to the terms of the CC0 1.0 Public Domain Dedication (http://creativecommons.org/publicdomain/zero/1.0/). This waiver does not extend to any page images or other supplementary files associated with this work, which may be protected by copyright or other license restrictions. Please go to http://www.textcreationpartnership.org/ for more information.
- Subject terms
- Mathematics -- Early works to 1800.
- Geometry -- Early works to 1800.
- Algebra -- Early works to 1800.
- Link to this Item
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http://name.umdl.umich.edu/A61912.0001.001
- Cite this Item
-
"Mathesis enucleata, or, The elements of the mathematicks by J. Christ. Sturmius ; made English by J.R. and R.S.S." In the digital collection Early English Books Online 2. https://name.umdl.umich.edu/A61912.0001.001. University of Michigan Library Digital Collections. Accessed June 21, 2025.
Pages
Page 141
IK=x; then will the angle IKA=F72°. Therefore the an∣gle AKO=108; and since KOA is 36°, KAO will be also 36°, and so KA=KO=AF=b. Wherefore OI is = b+x, which was above a−x. Therefore 2OI= 〈 math 〉〈 math 〉, i. e. a+b. Therefore OI= 〈 math 〉〈 math 〉.
Notes
-
(α) 1.1
Eucl. Prop. 1. lib. 14.