 | Euclides - 1842 - 316 pagina’s
...point A draw (Euc. 12. 1.) AD perpendicular to вc. If then AD be also perpendicular to the plane вн, the thing required is already done : but if it be not, from the point D draw (Euc. 11. 1.) in the plane вн, the straight line DE, at right angles to BC; and from the point A... | |
 | Euclid - 1845 - 218 pagina’s
...draw any straight line BC, and from the point A* draw AD perpendicular to BC. If then AD be * 12. i. also perpendicular to the plane BH, the thing required...is already done: but if it be not, from the point D drawf, t ni in the plane BH, the straight line DE at right angles to BC ; and from the point A draw... | |
 | Euclid, James Thomson - 1845 - 382 pagina’s
...BH. In the plane draw any straight line BC, and (I. 12) from A draw AD perpendicular to BC. Then, if AD be also perpendicular to the plane BH, the thing required is done. But if it be not, from D (I. 11) draw DE, in the plane BH, at right angles to BC ; from A draw... | |
 | Euclides - 1845 - 546 pagina’s
...In the plane draw any straight line BC, and from the point A draw AD perpendicular to BC. (i. 12.) If then AD be also perpendicular to the plane BH, the thing s required is already done ; but if it be not, from the point D draw, in the plane BH, the straight... | |
 | Euclid, John Playfair - 1846 - 334 pagina’s
...A draw (Prop. 12. 1.) ADpeipendicular to BC. If then AD be also perpendicular to the plane BH, *he thing required is already done ; but if it be not, from the point D draw (Prop. 11. 1.), in the plane BH, the straight line DE at right angles to BC ; and from the point A... | |
 | Euclides - 1846 - 292 pagina’s
...Draw any straight line BC in the plane BH, and from the point A draw AD perpendicular to BC : Then, if AD be also perpendicular to the plane BH, the thing required is done : But, if not, from D draw, in the plane BH, the straight line DE at right angles to BC ; and... | |
 | John Playfair - 1847 - 340 pagina’s
...from the point A draw (Prop. 12. 1.) ADpeipendicular to BC. If then AD be also perpendicular to tlie plane BH, the thing required is already done ; but if it be not, from the point D draw (Prop. 11. 1.), in the plane BH, the straight line DE at right angles to BC ; and from the point A... | |
 | Samuel Hunter Christie - 1847 - 172 pagina’s
...plane MN, and let BD be the common section of the first two: BD shall be perpendicular to the plane MN. If it be not, from the point D draw, in the plane AB, the straight line DE at right angles to AD (I. 11) the common section of the planes AB and MN;... | |
 | Euclides - 1855 - 230 pagina’s
...the base AC to the base DF. the angle ABC is equal to the ang(eVEF(d). PROPOSITION XI. PROBLEM.—To draw a straight line perpendicular to a plane (BH),...thing required is already done: but if it be not, from tlie point D draw, in the plane BH, the straight line DE at right angles to BC (6); and from the point... | |
 | Euclides - 1855 - 270 pagina’s
...perpendicular to the plane BH, what was required is done. But if it be not, from the point D draw (I. 1 1 ) in the plane BH, the straight line DE at right angles to B С; and in the plane passing through DE and A, from the point A, draw AF perpendicular to D E. AF... | |
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... plane, from a given point above it. Let A be the given point above the plane BH; it is required to draw from the point A a straight line perpendicular to the plane BH. 
