An introduction to the Elements of Euclid, being a familiar explanation of the first twelve propositions of the first book |
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Αποτελέσματα 1 - 5 από τα 30.
Σελίδα 28
... join on the second link of your ' chain of reasoning . ' The question ever to be asked , what is given , and what has to be done in the Second Proposition , is thus answered in the General Enunciation . Given a point , and a straight ...
... join on the second link of your ' chain of reasoning . ' The question ever to be asked , what is given , and what has to be done in the Second Proposition , is thus answered in the General Enunciation . Given a point , and a straight ...
Σελίδα 30
... joining A D and DB , The equilateral triangle being thus described , write down the next step of the construction , which is : 3. Produce the two sides DA , DB to the points E and F. ' This is done by Postulate 2 . Notice that both the ...
... joining A D and DB , The equilateral triangle being thus described , write down the next step of the construction , which is : 3. Produce the two sides DA , DB to the points E and F. ' This is done by Postulate 2 . Notice that both the ...
Σελίδα 35
... Join the given point with one end of the given straight line . [ Call this the joining line . ] 2. Upon this joining line as the base , describe an equi- lateral triangle . 3. Produce the two sides of this equilateral triangle . 4 ...
... Join the given point with one end of the given straight line . [ Call this the joining line . ] 2. Upon this joining line as the base , describe an equi- lateral triangle . 3. Produce the two sides of this equilateral triangle . 4 ...
Σελίδα 36
... joining line AC . The fourth by describing the equilateral triangle on the other side of the joining line A C.1 Fig ... join A to B or C , because these points are already joined ( A B and A C being parts of the given straight line B C ) ...
... joining line AC . The fourth by describing the equilateral triangle on the other side of the joining line A C.1 Fig ... join A to B or C , because these points are already joined ( A B and A C being parts of the given straight line B C ) ...
Σελίδα 39
... join HA , and to save time and ensure correctness , before removing the ruler , produce HA to any point K. In like manner join H C , and produce it at once to M. iii . The third step in the construction of the second pro- position is ...
... join HA , and to save time and ensure correctness , before removing the ruler , produce HA to any point K. In like manner join H C , and produce it at once to M. iii . The third step in the construction of the second pro- position is ...
Συχνά εμφανιζόμενοι όροι και φράσεις
A C is equal ABC and DEF adjacent angles angle A B C angle ABC angle ACB angle B A C angle BAC angle contained angles are equal bisected centre construction D E F Definition demonstration describe an equilateral Douglas White draw a straight drawn Eighth Proposition Eleventh Proposition equal sides equal to A C equal to CL equilateral triangle Euclid exercise figure five steps follows fourth proposition given equal given point given straight line greater included angles isosceles triangle join Particular Enunciation pencil Prop PROPOSITION WRITTEN proved equal radii remaining angles required to prove respect right angles second proposition set square sides A B sides are opposite sides BA Sixth Proposition space straight line A B three straight lines triangle ABC triangles are equal vertex Wherefore write
Δημοφιλή αποσπάσματα
Σελίδα 54 - If two triangles have two sides of the one equal to two sides of the...
Σελίδα 10 - When a straight line standing on another straight line makes the adjacent angles equal to one another, each of the angles is called a right angle ; and the straight line which stands on the other is called a perpendicular to it.
Σελίδα 10 - A circle is a plane figure contained by one line, which is called the circumference, and is such that all straight lines drawn from a certain point within the figure to the circumference, are equal to one another.
Σελίδα 103 - On the same base, and on the same side of it, there cannot be two triangles having their sides which are terminated at one extremity of the base equal to one another, and likewise those which are terminated at the other extremity equal to one another.
Σελίδα 83 - If two angles of a triangle be equal to one another, the sides also which subtend, or are opposite to, the equal angles, shall be equal to one another.
Σελίδα 123 - The neglect which he had shown of the elementary truths of geometry he afterwards regarded as a mistake in his mathematical studies ; and on a future occasion he expressed to Dr. Pemberton his regret that " he had applied himself to the works of Descartes, and other algebraic writers, before he had considered the Elements of Euclid with that attention which so excellent a writer deserved."3 The study of Descartes...
Σελίδα 89 - AC. For, if AB be not equal to AC, one of them is greater than the other : let AB be the greater, and from it cut (i.
Σελίδα 98 - Upon the same base, and on the same side of it, there cannot be two triangles that have their sides which are terminated in one extremity of' the base, equal to one another, and likewise those which are terminated in the other extremity.
Σελίδα 11 - A diameter of a circle is a straight line drawn through the centre, and terminated both ways by the circumference.
Σελίδα 4 - A plane rectilineal angle is the inclination of two straight lines to one another, which meet together, but are not in the same straight line.