| Perry Fairfax Nursey - 1831 - 508 pages
...has been before proved that the angle ADe is an acute angle of 90 degrees, whence it follows that as **the three angles of a triangle are together equal to two right angles, the** remaining angle /AD must likewise be an acute angle of 90 degrees, and, as before, since the two angles/... | |
| Francis Lieber, Edward Wigglesworth - 1832 - 656 pages
...numbers. Of tho geometrical theorems which are ascribed to him, the following are the most important : **The three angles of a triangle are together equal to two right angles** ; and in aright-angled triangle, the square of the hypothenuse is equal to the sum of the squares of... | |
| Francis Lieber, Edward Wigglesworth, Thomas Gamaliel Bradford - 1832 - 708 pages
...numhcfs. Of tho geometrical theorems which are ascribed to him, the following are the most important : **The three angles of a triangle are together equal to two right angles** ; and in a right-angled triangle, the square of the hypothenuse is equal to the sum of the squares... | |
| Leonhard Euler, Sir David Brewster - 1833 - 446 pages
...impossible to draw any conclusion with respect to real objects; thus, when I have demonstrated that **the three angles of a triangle are together equal to two right angles,** this is a property belonging only to an abstract triangle, and not at all to one really existing. You... | |
| Leonhard Euler, Sir David Brewster - 1833 - 442 pages
...impossible to draw any conclusion with respect to real objects ; thus, when I have demonstrated that **the three angles of a triangle are together equal to two right angles,** this is a property belonging only to an abstract triangle, and not at all to one really existing. 32... | |
| 1833 - 504 pages
...advanced as far as the thirty-second proposition of the first book of Euclid. He had perceived that **the three angles of a triangle are together equal to two right** ones, and was searching for a satisfactory proof, when his father surprised him in his forbidden speculations.... | |
| 1835 - 684 pages
...notwithstanding, of opinion, that the grand truth with which it is so intimately connected, viz., that " **the three angles of a triangle are together equal to two right angles,"** may be referred to the general principle of Homogeneity. Of this it is unnecessary to say more in this... | |
| American Institute of Instruction - 1836 - 328 pages
...for a thousand years, furnishes no absolute assurance that it will rise tomorrow. But the truth that **the three angles of a triangle are together equal to two right angles,** is made as certain by a single demonstration, as it could be by a thousand. Apply now this illustration... | |
| American Institute of Instruction - 1836 - 332 pages
...for a thousand years, furnishes no absolute assurance that it will rise tomorrow. But the troth that **the three angles of a triangle are together equal to two right angles,** ia made as certain by a single demonstration, as it could be by a thousand. Apply now this illustration... | |
| Leonhard Euler - 1837 - 452 pages
...impossible to draw any conclusion with respect to real objects ; thus, when I have demonstrated that **the three angles of a triangle are together equal to two right angles,** this i^ a property belonging only to an abstract triangle, and not at all to one really existing. last,... | |
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