| Robert Simson - Trigonometry - 1806 - 546 pages
...besides FC, that is, FC is perpendicular to DE. Therefore, if a straight line, 6cc. QED PROP. XIX. THEOR. IF a straight line touches a circle, and from the point of contact a straight line be drawn at right angles to the touching line, the centre of the circle shall be in that line. if possible,... | |
| John Playfair - Mathematics - 1806 - 320 pages
...Therefore, if a straight line, &c. QED a 17. 1. b 19. i. PROP. XIX. THEOR. IF a straight line touch a circle, and from the point of contact a straight line be drawn at right angles to the touching line, the centre of the circle is in that line. Book III. Let the straight... | |
| Euclid - Geometry - 1810 - 554 pages
...Therefore, if a straight line, &c. QED C GE a 18. 3. ,' PROP. XIX. THEOR. IF a straight line touch a circle, and from the point of contact a straight line be drawn at right angles to the touching lirie, the centre of the circle shall be in that line. Let the straight... | |
| John Mason Good - 1813 - 714 pages
...to the point of contact, shall be perpendicular to the line touching the circle. Prop. XIX. Theor. If a straight line touches a circle, and from the point of contact a straight line be drawn at right angles to the. touching line, the centro of the circle shall be in that line. Prop. XX. Theor.... | |
| Euclides - 1816 - 588 pages
...that is, FC is perpendicular to DE. Therefore if a straight , . line^&c. QED D" c PROP. XIX. THEOR. IF a straight line touches a circle, and from the point of contact a straight line be drawn at right angles to the touching line, the centre of the circle shall be in that line. Let the straight... | |
| John Mason Good - 1819 - 800 pages
...less than a semicircle is greater than a right angle. Prop. XXX IL Thcor. If a straight line touche» a circle, and from the point of contact a straight line be drawn culling the circle, the angles made by this line with the line touching the circle, shall be equal... | |
| John Playfair - Circle-squaring - 1819 - 350 pages
...perpendicular to DE. Therefore, if a straight line, &c. Q, ED PROP. XIX. THEOR. If a straight line touch a circle, and from the point of contact a straight line be drawn at right angles to the touching line, the centre of the circle, is in that line. Let the straight line... | |
| Euclides - 1821 - 294 pages
...PROP. 3S, THEOR. If a right line be a tangent to a circle, and from the, jpoint of contact a right line be drawn cutting the circle, the angle made by this line with the tangent, ts equal to the angle in the alternate segment of the circle. If the secant should pass through... | |
| Peter Nicholson - Mathematics - 1825 - 1046 pages
...that is, FC is perpendicular to DE. Therefore, if a straight line, &c. QED Proposition XIX. Tliearem. If a straight line touches a circle, and from the point of contact a straight line be drawn at right angles to the touching line, the centre of the circle shall be in that line. Let the straight... | |
| Robert Simson - Trigonometry - 1827 - 546 pages
...perpendicular to I>E. Therefore, if a straight line, &c. QED PROP. XIX. THEOR. If a straight line taucJ1es a circle and from the point of contact a straight line be drawn at right angles to the touching line, the centre of the circle shall be in that line. Let the straight... | |
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