A school Euclid, being books i. & ii. of Euclid's Elements, with notes by C. Mansford1874 |
From inside the book
Results 1-5 of 14
Page v
... Hence it is that the definitions are placed at the very commencement , and it is important that their meaning and their proper relation to the propositions which follow should be clearly understood . DEFINITIONS . Let it be observed ...
... Hence it is that the definitions are placed at the very commencement , and it is important that their meaning and their proper relation to the propositions which follow should be clearly understood . DEFINITIONS . Let it be observed ...
Page ix
... hence are sometimes classed with the postulates ; while the first nine axioms are common notions ' which are true of all magnitudes whatever . The twelfth axiom may be more simply expressed thus , " Two straight lines which cut one ...
... hence are sometimes classed with the postulates ; while the first nine axioms are common notions ' which are true of all magnitudes whatever . The twelfth axiom may be more simply expressed thus , " Two straight lines which cut one ...
Page xi
... hence what is asserted of all right angles may be asserted concerning them , viz . that they are equal to one another . Now as all geometrical proofs may be reduced to a series of processes similar to the above in which the truth of the ...
... hence what is asserted of all right angles may be asserted concerning them , viz . that they are equal to one another . Now as all geometrical proofs may be reduced to a series of processes similar to the above in which the truth of the ...
Page 23
... Hence the triangle ABC coin- cides with DEF . This is one of the most important results in Book I. Ex . 1. Prove by the method used in this proposition that the two triangles into which a square is divided by its diagonal are equal to ...
... Hence the triangle ABC coin- cides with DEF . This is one of the most important results in Book I. Ex . 1. Prove by the method used in this proposition that the two triangles into which a square is divided by its diagonal are equal to ...
Page 25
... Hence every equilateral triangle is also equiangular . If the pupil finds serious difficulty in mastering this proposi- tion , it will probably be a help to distinguish the triangles spoken of by shading . Or two figures may be drawn ...
... Hence every equilateral triangle is also equiangular . If the pupil finds serious difficulty in mastering this proposi- tion , it will probably be a help to distinguish the triangles spoken of by shading . Or two figures may be drawn ...
Other editions - View all
A School Euclid, Being Books I. & II. of Euclid's Elements, with Notes by C ... Euclides No preview available - 2015 |
Common terms and phrases
AC is equal adjacent angles alternate angles angle ABC angle ACB angle AGH angle BAC angle BCD angle DBA angle EDF angle equal angles are equal axioms base BC bisect centre circle coincide Const diagonals diameter double equal sides equal to BC equal to twice equilateral triangle Euclid EUCLID'S ELEMENTS exterior angle fore four right angles given point given rectilineal angle given straight line gnomon half a right hypotenuse interior and opposite isosceles triangle join Let ABC Let the straight obtuse opposite angle opposite sides parallel to CD parallelogram parallelogram ABCD perpendicular produced prop quadrilateral rectangle AC rectangle contained remaining angle rhombus right angles right-angled triangle shew side BC sides equal square described square on AC THEOREM third angle triangle ABC triangle DEF truths twice the rectangle unequal
Popular passages
Page 90 - If a straight line be divided into any two parts, the squares of the whole line, and of one of the parts, are equal to twice the rectangle contained by the whole and that part, together with the square of the other part.
Page 28 - If two triangles have two sides of the one equal to two sides of the...
Page 41 - Any two sides of a triangle are together greater than the third side.
Page 57 - IF a side of any triangle be produced, the exterior angle is equal to the two interior and opposite angles; and the three interior angles of every triangle are equal to two right angles.
Page 72 - To describe a parallelogram equal to a given rectilineal figure, and having an angle equal to a given rectilineal angle. Let ABCD be the given rectilineal figure, and E the given rectilineal angle. It is required to describe a parallelogram equal to ABCD, and having an angle equal to E.
Page 75 - In any right-angled triangle, the square which is described upon the side subtending the right angle, is equal to the squares described upon the sides which contain the right angle.
Page 89 - If a straight line be bisected, and produced to any point ; the rectangle contained by the whole line thus produced, and the part of it produced...
Page 55 - IF a straight line fall upon two parallel straight lines, it makes the alternate angles equal to one another; and the exterior angle equal to the interior and opposite upon the same side; and likewise the two interior angles upon the same side together equal to two right angles...
Page 28 - A two triangles, having the two sides AB, AC, equal to the two sides \ DE, DF, each to each, viz: AB to DE, and AC to DF; and also the base BC equal to the base EF.
Page 69 - 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.