| John Playfair - 1819 - 350 sider
...&c. Q, ED PROP. XVII. THEOR. Jlny too angles of a triangle are together less than two right angle's. Let ABC be any triangle ; any two of its angles together are less than two right angles. Produce BC'to D ; and because ACD is the exterior angle of the triangle ABC, ACD is greater (16. 1.) than the... | |
| John Playfair - 1819 - 354 sider
...BCG, that is (15. 1.), the angle ACD, is greater than the angle ABC. Therefore, if one side, &c. Q, ED PROP. XVII. THEOR. - Any two angles of a triangle are together less than' two right angle*. Let A BC be any triangle ; any two of its angles together are less than two right angles. Produce... | |
| 1854 - 1112 sider
...proved hereafter, it is here inserted in order to facilitate the theory of parallel lines. Cor. 2. Any two angles of a triangle are together less than two right angles. For either is less than the supplement of the other. Cor. 3. If any angle of a triangle is right or... | |
| Euclid, John Playfair - 1826 - 326 sider
...if one Bide, <SeQED 4 PROP. XVII. t HEOR. Any two angles of a triangle are together less than twfl right angles. Let ABC be any triangle; any two of...its angles together are less than two right angles. Produee BC to D ; and beeause ACD is the exterior angle of the triangle ABC, ACD, is greater (16. 1.)... | |
| George Lees - 1826 - 276 sider
...that the angle BCG, that is, ACD% is e 5. 1. greater than ABC. Therefore, if one side, &c. QED Cor. Any two angles of a triangle, are together less than two right angles. For, since by the proposition, the exterior angle ACD is greater than the interior and opposite angle... | |
| Pierce Morton - 1830 - 584 sider
...the one equal to the three sides of the other, each to each, are equul in all respects . . 7 (•7) Any two angles of a triangle are together less than two right angles 7 (A} A triangle cannot have more than one right angle, or more than one obtuse angle . . nor. 7 (i)... | |
| Augustus De Morgan - 1831 - 108 sider
...than two right angles, is not an assumption but a consequence of his proposition, which shews that any two angles of a triangle are together less than two right angles, and which is established before any mention is made of parallels. It has been found by the experience... | |
| Euclides - 1833 - 304 sider
...line. For then an external angle would be = to an internal and opposite, which is absurd. PROP. 17, THEOR. Any two angles of a triangle are together less than two right angles. Produce any side ; then the external angle is greater than either of the internal remote angles ; but... | |
| Thomas Perronet Thompson - 1833 - 168 sider
...And by parity of reasoning, the like may be proved in every other triangle. Wherefore, universally, any two angles of a triangle are together less than two right angles. Which was to be demonstrated. COH. 1. A triangle cannot have more than one right angle; nor more than... | |
| Euclides - 1834 - 518 sider
...side, &e. OED PROPOSITION XVII. THEOR. — Any two angles of a triangle are together lest than Iwo right angles. Let ABC be any triangle : any two of its angles together shall be less than two right angles. Produce BC to D : and because ACD is the exterior angle of the... | |
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