| Charles Davies - Geometry - 1850 - 218 pages
...three to 120°x3r=360°0 GEOMETRY. BOOK V. OF PLANES AND THEIR ANGLES* DEFINITIONS. 1 . A straight **line is perpendicular to a plane, when it is perpendicular to every** straight line of the plane which it meets. The point at which the perpendicular meets the plane, is... | |
| Charles Davies - Geometry - 1886 - 334 pages
...the three to 120° X 3= 360" GEOMETRY. BOOK V. OF PLANES AND THE1B ANGLES. DEF1N1T1ONS. 1. A straight **line is perpendicular to a plane, when it is perpendicular to every** straight line of the plane which it meets. The point at which the perpendicular meets the plane, is... | |
| Charles Davies - Geometry - 1854 - 436 pages
...always be placed as in the f1gure. BOOK VI. PLANES AND POLYEDRAL ANGLES. DEFINITIONS. 1. A straight **line is perpendicular to a plane, when it is perpendicular to every** straight line of the plane which passes through its foot : conversely, the plane is perpendicular to... | |
| Charles Davies, William Guy Peck - Mathematics - 1855 - 630 pages
...tangent to the curve at the point of contact. Such a line is generally called a normal. Л straight **line is perpendicular to a plane when it is perpendicular to every** straight line drawn through its foot in that plane. A straight line is perpendicular to a curved surface... | |
| Elias Loomis - Conic sections - 1858 - 252 pages
...signifies circumference. SOLID GEOMETRY, BOOK VII. PLANES AND SOLID ANGLES Definitions. 1. A STRAIGHT **line is perpendicular to a plane, when it is perpendicular to every** straight line which it meets in that plane. Conversely, the plane in this case is per pendicular to... | |
| George Roberts Perkins - Geometry - 1860 - 468 pages
...obvious, from our definition of a plane (BI, D. XVII.), that this intersection is a straight line. II. **A line is perpendicular to a plane, when it is perpendicular to** all the lines in that plane which meet it. III. One plane is perpendicular to another, when every line... | |
| Benjamin Greenleaf - Geometry - 1861 - 628 pages
...English mathematician. OOK VII. PLANES. — DIEDRAL AND TOLTEDRAL ANGLES. DEFINITIONS. 888. A STRAIGHT **line is perpendicular to a plane, when it is perpendicular to every** straight line which it meets in that plane. Conversely, the plane, in the same case, is perpendicular... | |
| Benjamin Greenleaf - Geometry - 1862 - 520 pages
...English mathematician. BOOK VII. PLANES. — DIEDRAL AND P0LYEDRAL ANGLES. DEFINITIONS. 388. A STRAIGHT **line is perpendicular to a plane, when it is perpendicular to every** straight line which it meets in that plane. Conversely, the plane, in the same case, is perpendicular... | |
| Olinthus Gregory - 1863 - 482 pages
...perpendicular to a plane, when it is perpendi cular to every line in that plane which meets it. 3. **One plane is perpendicular to another, when every...their common section, is perpendicular to the other.** 4. The inclination of one plane to another, or the angle they form between them, is the angle contained... | |
| Adrien Marie Legendre - Geometry - 1863 - 464 pages
...exactly equal to that of the circle. BOOK VI. FLAKES AND POLYEDRAL ANGLES. DEFINITIONS. 1. A straight **line is PERPENDICULAR TO A PLANE, when it is perpendicular to every line** of the plane which passes through its FOOT ; that is, through the point in which it meets the plane.... | |
| |