The First Six Books of the Elements of Euclid: And Propositions I-XXI of Book XI, and an Appendix on the Cylinder, Sphere, Cone, Etc., with Copious Annotations and Numerous ExercisesHodges, Figgis, & Company, 1885 - 312 páginas |
Dentro del libro
Resultados 1-5 de 44
Página 19
... external angles ( DBC , ECB ) below the base shall be equal . Dem . - In BD take any point F , and from AE , tl e greater , cut off AG equal to AF [ 11 ] . Join BG , CF ( Post . I. ) . Because AF is equal to AG ( const . ) , and AC is ...
... external angles ( DBC , ECB ) below the base shall be equal . Dem . - In BD take any point F , and from AE , tl e greater , cut off AG equal to AF [ 11 ] . Join BG , CF ( Post . I. ) . Because AF is equal to AG ( const . ) , and AC is ...
Página 23
... external angles ECD , FDC at the other side of the base CD are equal ; but ECD is greater than BCD ( Axiom IX . ) . There- fore FDC is greater than BCD much more is BDC greater than BCD ; but if BC were equal E F B to BD , the angle BDC ...
... external angles ECD , FDC at the other side of the base CD are equal ; but ECD is greater than BCD ( Axiom IX . ) . There- fore FDC is greater than BCD much more is BDC greater than BCD ; but if BC were equal E F B to BD , the angle BDC ...
Página 35
... 4. If the lines be drawn to any point in the bisector of the external vertical angle , their sum is greater than the sum of the sides . 5. Any side of any polygon is less than the D 2 BOOK I. ] THE ELEMENTS OF EUCLID . 35.
... 4. If the lines be drawn to any point in the bisector of the external vertical angle , their sum is greater than the sum of the sides . 5. Any side of any polygon is less than the D 2 BOOK I. ] THE ELEMENTS OF EUCLID . 35.
Página 36
... the sum of BA , AC is greater than the sum of BE , EC . Therefore much more is the sum of BA , AC greater than the sum of BD , DC . B C 2. The external angle BDC of the triangle DEC is 36 [ BOOK I. THE ELEMENTS OF EUCLID .
... the sum of BA , AC is greater than the sum of BE , EC . Therefore much more is the sum of BA , AC greater than the sum of BD , DC . B C 2. The external angle BDC of the triangle DEC is 36 [ BOOK I. THE ELEMENTS OF EUCLID .
Página 37
... external angle BDC of the triangle DEC is greater than the internal angle BEC [ xvI . ] , and the angle BEC , for a like reason , is greater than BAC . Therefore much more is BDC greater than BAC . Part 2 may be proved without producing ...
... external angle BDC of the triangle DEC is greater than the internal angle BEC [ xvI . ] , and the angle BEC , for a like reason , is greater than BAC . Therefore much more is BDC greater than BAC . Part 2 may be proved without producing ...
Otras ediciones - Ver todas
Términos y frases comunes
ABCD AC is equal adjacent angles altitude angle ABC angle ACB angle BAC angular points Axiom bisector bisects centre chord circles touch circumference circumscribed circle collinear concurrent lines const coplanar cyclic quadrilateral Dem.-Let diagonals diameter divided draw equal angles equal to AC equiangular equilateral triangle escribed circles Euclid Exercises exterior angle Geometry given circle given line given point greater Hence the angle hypotenuse inscribed less line AC line joining locus manner meet middle points multiple nine-points circle opposite sides parallel parallelogram parallelopiped perpendicular plane points of intersection prism PROP Proposition prove radii radius rectangle contained rectilineal figure regular polygon respectively equal right angles right line segments semicircle sides AC similar square on AC tangent theorem triangle ABC vertex vertical angle
Pasajes populares
Página 299 - Thus the proposition, that the sum of the three angles of a triangle is equal to two right angles, (Euc.
Página 186 - When of the equimultiples of four magnitudes (taken as in the fifth definition) the multiple of the first is greater than that of the second, but the multiple of the third is not greater than the multiple of the fourth ; then the first is said to have to the second a greater ratio than the third magnitude has to the fourth...
Página 9 - LET it be granted that a straight line may be drawn from any one point to any other point.
Página 104 - To divide a given straight line into two parts, so that the rectangle contained by the whole and one of the parts, shall be equal to the square on the other part.
Página 124 - The diameter is the greatest straight line in a circle; and, of all others, that which is nearer to the centre is always greater than one more remote; and the greater is nearer to the centre than the less. Let ABCD be a circle, of which...
Página 230 - If from any angle of a triangle, a straight line be drawn perpendicular to the base ; the rectangle contained by the sides of the triangle is equal to the rectangle contained by the perpendicular and the diameter of the circle described about the triangle.
Página 29 - Again ; the mathematical postulate, that " things which are equal to the same are equal to one another," is similar to the form of the syllogism in logic, which unites things agreeing in the middle term.
Página 63 - To a given straight line to apply a parallelogram, which shall be equal to a given triangle, and have one of its angles equal to a given rectilineal angle.
Página 128 - The diagonals of a quadrilateral intersect at right angles. Prove that the sum of the squares on one pair of opposite sides is equal to the sum of the squares on the other pair.
Página 22 - ACB, DB is equal to AC, and BC common to both ; the two sides DB, BC, are equal to the two AC, CB, each to each, and the angle DBC is equal to the angle ACB : therefore, the base DC is equal to the base AB, and the triangle DBC (Mr. Southey) is equal to the triangle ACB, the less to the greater, which is absurd,