The Elements of Euclid: With Dissertations Intended to Assist and Encourage a Critical Examination of These Elements as the Most Effectual Means of Establishing a Juster Taste Upon Mathematical Subjects Than that which at Present Prevails |
From inside the book
Results 6-10 of 48
Page 49
... fall beyond the point B. And indeed it is very difficult to under- stand any general propofition , without fome representation of all the different pofitions which the lines can take and the reader cannot finish this propofition better ...
... fall beyond the point B. And indeed it is very difficult to under- stand any general propofition , without fome representation of all the different pofitions which the lines can take and the reader cannot finish this propofition better ...
Page 60
... falling infinitely short of his idea of demonftration : where- fore without perplexing his reader with impotent attempts towards a demonstration ; he judged it more proper to cut short this fruit- let's fearch by placing this principle ...
... falling infinitely short of his idea of demonftration : where- fore without perplexing his reader with impotent attempts towards a demonstration ; he judged it more proper to cut short this fruit- let's fearch by placing this principle ...
Page 61
... there → fore , that it would be unfair in him , to appropriate to himself either the notions or their confequences ; or according to Clairaut , thatt that such reasonings would only fall upon , what good DISSERTATION III . 61.
... there → fore , that it would be unfair in him , to appropriate to himself either the notions or their confequences ; or according to Clairaut , thatt that such reasonings would only fall upon , what good DISSERTATION III . 61.
Page 62
... fall upon , what good sense had de- cided before hand , in a manner full as fatisfactory . Again , there is an inftance of the fame kind , in the twenty fourth propofition ; where the most material part of the fuppofi- tion is never ...
... fall upon , what good sense had de- cided before hand , in a manner full as fatisfactory . Again , there is an inftance of the fame kind , in the twenty fourth propofition ; where the most material part of the fuppofi- tion is never ...
Page 64
... falls within the tri- angle , the conclufion may be inferred from the twenty first propo- fition ; but it would be more uniform to produce DF and DG ; and to reafon upon the angles below the base , in the fame manner as Euclid has done ...
... falls within the tri- angle , the conclufion may be inferred from the twenty first propo- fition ; but it would be more uniform to produce DF and DG ; and to reafon upon the angles below the base , in the fame manner as Euclid has done ...
Other editions - View all
The Elements of Euclid: With Dissertations Intended to Assist and Encourage ... James Williamson,James Euclid No preview available - 2016 |
Common terms and phrases
ABCD alfo alſo angle ABC angle BAC angle contained angle equal apply itſelf bafe baſe BC is equal Book certainly circle ABC circumference common notion confequences conft conftruction cut in halves demonftrated deſcribed diſtance drawn equal angles equiangular equilateral equimultiples Euclid exceed faid fame manner fame multiple fame parallels fame ratio fame reaſon fecond fegment fhall fides fimilar fince firſt fome fquare ftraight line BC fuch fuppofe fuppofition given rectilineal given ſtraight line Gnomon greater hath himſelf impoffible infcribed joined lefs leſs let the ftraight magnitudes moſt muſt neceffary parallelogram PROP propofition proportionals purpoſe reader reaſon rectangle contained rectilineal figure remaining angle remaining fides right angles ſame ſay ſhall ſhould ſome ſquare ſtraight line AB ſubject ſuch ſuppoſe taken theſe thoſe tiple triangle ABC underſtand uſe Wherefore becauſe
Popular passages
Page 3 - Let it be granted that a straight line may be drawn from any one point to any other point.
Page 47 - If there be two straight lines, one of which is divided into any number of parts, the rectangle contained by the two straight lines is equal to the rectangles contained by the undivided line, and the several parts of the divided line. Let...
Page 68 - If a straight line drawn through the centre of a circle bisect a straight line in it which does not pass through the centre, it shall cut it at right angles : and if it cut it at right angles, it shall bisect it.
Page 45 - ABG ; (vi. 1.) therefore the triangle ABC has to the triangle ABG the duplicate ratio of that which BC has to EF: but the triangle ABG is equal to the triangle DEF; therefore also the triangle ABC has to the triangle DEF the duplicate ratio of that which BC has to EF. Therefore similar triangles, &c.
Page 15 - When a straight line set up on a straight line makes the adjacent angles equal to one another, each of the equal angles is right, and the straight line standing on the other is called a perpendicular to that on which it stands.
Page 86 - When you have proved that the three angles of every triangle are equal to two right angles...
Page 88 - EA : and because AD is equal to DC, and DE common to the triangles ADE, CDE, the two sides AD, DE are equal to the two CD, DE, each to each ; and the angle ADE is equal to the angle CDE, for each of them is a right angle ; therefore the base AE is equal (4.
Page 42 - If four straight lines be proportionals, the rectangle contained by the extremes is equal to the rectangle contained by the means ; And if the rectangle contained by the extremes be equal to the rectangle contained by the means, the four straight lines are proportionals. Let the four straight lines, AB, CD, E, F, be proportionals, viz.
Page 109 - Draw two diameters AC, BD of the circle ABCD, at right angles to one another; and through the points A, B. C, D, draw (17.
Page 8 - GB is equal to E, and CK to F ; therefore AB is the same multiple of E, that KH is of F: But AB...