| Euclid - Euclid's Elements - 1789 - 296 pages
...1. The common fection of two planes, is the line in which they meet, or cut each other. 2. A right **line is perpendicular to a plane, when it is perpendicular to every** right line which meets it in that plane. 3. A plane is perpendicular to a plane, when every right line... | |
| Charles Hutton - Astronomy - 1815 - 686 pages
...perpendicular to a curve, when it is perpendicular to the tanpent of the curve at the point of con- =, tact. **A line is perpendicular to a plane, when it is perpendicular to every line** drawn in the plane through the bottom of the perpendicular. And one plane is perpendicular to another,... | |
| Encyclopedias and dictionaries - 1816
...THE COMMON SECTION of two planes, is the line in which tht-r meet, or cut each other. 68. A ftraight **line is PERPENDICULAR, to. a plane, when it is perpendicular to every line** which meets it in that plane. 69. One plane is PERPENDICULAR to another, vhen every right line in the... | |
| Adrien Marie Legendre - Geometry - 1819 - 208 pages
...FIRST. '• ' . : .'•!. ..',•. - : V. -. '-.I Of planes and solid angles. .... . . 313. A 8TRAIGHT **line is perpendicular to a plane, when it is perpendicular to every** straight line in the plane which passes through the foot of the perpendicular (326). Reciprocally,... | |
| Pierre Simon marquis de Laplace, Thomas Young - Celestial mechanics - 1821 - 388 pages
...radius being unity, 1°=:.01 7453293, 1'=.000290888, and 1"=: .000004848. 145. DEFINITION. A straight **line is perpendicular to a plane, when it is perpendicular to every** straight line meeting it in that plane. 146. DEFINITION. A plane is perpendicular to a plane, when... | |
| Adrien Marie Legendre - Geometry - 1825 - 224 pages
...same perimeter. PART SECOND. SECTION FIRST. Of Planes and Solid Jingles. DEFINITIONS. 313. A STRAIGHT **line is perpendicular to a plane, when it is perpendicular to every** straight line in the plane which passes through the foot of the perpendicular (326). Reciprocally,... | |
| Adrien Marie Legendre, John Farrar - Geometry - 1825 - 280 pages
...same perimeter. PART SECOND. SECTION FIRST. Of Planes and Solid Angles, DEFINITIONS. 313. A STRAIGHT **line is perpendicular to a plane, when it is perpendicular to every** straight line in the plane which passes through the foot of the perpendicular (326). Reciprocally,... | |
| Ferdinand Rudolph Hassler - Electronic book - 1828 - 180 pages
...designated by length, breadth, and thickness. 2. Solids are bounded by surfaces, either plane or curved. 3. **A line is perpendicular to a plane: when it is perpendicular to every line** that can be drawn, in that plane, through its point of intersection with the same. 4. A plane is perpendicular... | |
| Zadock Thompson - Arithmetic - 1828 - 236 pages
...Planes, is tht line in which they meel, to cut each other. A Line is Perpendicular to a Plane, \\her. **it is perpendicular to every line in that plane which meets it.** One Plane is Perpendicular to Another when every line of the one, which h perpen dicular to the line... | |
| John Playfair - Geometry - 1829 - 186 pages
...ELEMENTS OF GEOMETRY. BOOK XI. OF THE INTERSECTION OF PLANES. DEFINITIONS.— See Notes. 1. A straight **line is perpendicular to a plane, when it is perpendicular to every** straight line meeting it in that plane. 2. A plane is perpendicular to a plane, when all the straight... | |
| |