AB, CD. In like manner, it may be proved, that FE makes right angles with every straight line which meets it in that plane. But a straight line is at right angles to a plane when it makes right angles with every straight line which meets it in that plane... Books 10-13 and appendix - Page 279by Euclid, Sir Thomas Little Heath, Johan Ludvig Heiberg - 1908Full view - About this book
| John Playfair - 1819 - 317 pages
...SUPPLEMENT. BOOK II. I OF THE INTERSECTION OF PLANES. DEFINITIONS. I. A STRAIGHT line is perpendicular, or **at right angles to a plane, when it makes right angles with** every straight line which it meets in that plane. II. A plane is perpendicular to a plane, when the... | |
| Abraham Rees - Encyclopedias and dictionaries - 1819
...2. The exterior furface of a folid is called its fuperficiee, 3 A ftraight line is perpendicular or **at right angles to a plane, when it makes right angles with** every ftraight line meeting it in that plane. 4. A plane is perpendicular to a plane, when the ftraight... | |
| George Crabb - Industrial arts - 1823
...That which bounds a solid is a plane, or a plane superficies. — A straight line is perpendicular, or **at right angles to a plane when it makes right angles with** every straight line meeting it in that plane, as AB in fig. 36. — A plane is perpendicular to a plane... | |
| Peter Nicholson - Mathematics - 1825 - 372 pages
...it may be proved, that FE makes right angles with every straight line which meets it in that plane. **But a straight line is at right angles to a plane when it makes right angles with** every straight line which meets it in that plane (3. def. 11.): Therefore KF is at riffht angles to... | |
| Robert Simson - Trigonometry - 1827 - 513 pages
...it may be proved, that FE makes right angles with every straight line which, meets it in that plane. **But a straight line is at right angles to a plane when it makes right angles with** every straight line which meets it in that plane*: therefore *3Def. n. EF is at right angles to the... | |
| Euclides - 1834
...it may be proved, that FE makes right angles with every straight line which meets it in that plane. **But a straight line is at right angles to a plane when it makes** fight angles with every straight line • 3 Def. 11. which meets it in that plane * : therefore EF... | |
| Euclid, John Davidson - Mathematics - 1835 - 513 pages
...it may be proved, that FE makes right angles with every straight line which meets it in that plane. **But a straight line is at right angles to a plane, when it makes right angles with** every straight Tine which meets it in that plane f: Therefore EF is at right f3.def.ll. angles to the... | |
| Jeremiah Day - Mathematics - 1836 - 472 pages
...the diameter contains seventy one. BOOK ii. — DEFINITIONS. 1. A straight line is perpendicular or **at right angles to a plane, when it makes right angles with** every straight line which it meets in that plane. 2. A plane is perpendicular to a plane, when the... | |
| William Whewell - 1837
...Props, i, n, in, A, iv of this Book vi. EUCLID, BOOK XI. DEF. 1. A straight line is perpendicular or **at right angles to a plane, when it makes right angles with** every straight line meeting it in that plane. DEF. 2. A plane is parallel to another plane when they... | |
| A. Bell, Robert Chambers, William Chambers - Conic sections - 1837 - 164 pages
...represented by means of diagrams drawn on a plane. DEFINITIONS. 1. A straight line is perpendicular, or **at right angles to a plane, when it makes right angles with** every straight line meeting it in that plane. 2. A plane is perpendicular to a plane, when the straight... | |
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