 | Jeremiah Day - Algebra - 1820 - 350 pages
...equations, though they may not be presented to us under the algebraic forms. Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 32. 1.) may be demonstrated, either in common language, or by means of the... | |
 | Jeremiah Day - Algebra - 1827 - 352 pages
...equations, though they may not be presented to us under the algebraic forms. Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 32. 1.) may be demonstrated, either in common language, or by means of the... | |
 | Charles William Hackley - Trigonometry - 1838 - 350 pages
...to 47°, and the other equal to 105° 30', it will be easy to find the third angle, by recollecting that the sum of the three angles of a triangle is equal to two right angles (Geom. B. 1, Prop. 25,) or 180° ; therefore subtracting the sum of the two given,... | |
 | Samuel Griswold Goodrich - Astronomy - 1844 - 370 pages
...in which some property is asserted, and the truth of it required to be proved : thus when it is said that the sum of the three angles of a triangle is equal to two right angles, that is a theorem, the truth of which is demonstrated by geometry. A set, or collection,... | |
 | James Bates Thomson - Algebra - 1844 - 266 pages
...equations, though they may not be presented to us under the algebraic forms. Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 32. 1,) may be demonstrated, either in common language, or by means of the... | |
 | Blaise Pascal - Apologetics - 1846 - 400 pages
...other, he gradually arrived at the proof of the thirty-second proposition of the first book of Euclid : That the sum of the three angles of a triangle is equal to two right angles. Just at this moment, his father entered the apartment ; but so absorbed in thought... | |
 | Jeremiah Day - Algebra - 1847 - 358 pages
...equations, though they may not be presented to us under the algebraic forms. Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 32. 1.) may be demonstrated, either in common language, or by means of the... | |
 | Jeremiah Day, James Bates Thomson - Algebra - 1848 - 264 pages
...equations, though they may not be presented to us under the algebraic forms. Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc. 32. 1,) may be demonstrated, either in common language, or by means of the... | |
 | Charles William Hackley - Trigonometry - 1851 - 524 pages
...to 47°, and the other equal to 105° 30', it will be easy to find the third angle, by recollecting that the sum of the three angles of a triangle is equal to two right angles (Geom. Theorem 15), or 180° ; therefore subtracting the sum of the two given, 47°... | |
 | Samuel Griswold Goodrich - Children's literature - 1852 - 372 pages
...in which some property is asserted, and the truth of it required to be proved : thus when it is said that the sum of the three angles of a triangle is equal to two right angles, that is a theorem, the truth of which is demonstrated hy geometry. A set, or collection,... | |
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After remarking that the mathematician positively knows that the sum of the three angles of a triangle is equal to two right angles... 
