Elements of Geometry and Plane Trigonometry: With an Appendix, and Copious Notes and IllustrationsA. Constable & Company, 1817 - 432 Seiten |
Im Buch
Ergebnisse 1-5 von 100
Seite 16
... draw the straight line BF : The angle ABC is bisected by BF . For the two triangles DBF and EBF , having the side DB ... drawing a perpendicular from a given point B in the straight line AC ; for the angle ABC , which the opposite seg ...
... draw the straight line BF : The angle ABC is bisected by BF . For the two triangles DBF and EBF , having the side DB ... drawing a perpendicular from a given point B in the straight line AC ; for the angle ABC , which the opposite seg ...
Seite 20
... draw ( I. 5. ) BD bisecting the vertical angle ABC . Because , by hypothesis , AB is equal to BC , the side BD common to the two tri- angles BDA and BDC , and the angles ABD and CBD contained by them are equal ; these triangles are ...
... draw ( I. 5. ) BD bisecting the vertical angle ABC . Because , by hypothesis , AB is equal to BC , the side BD common to the two tri- angles BDA and BDC , and the angles ABD and CBD contained by them are equal ; these triangles are ...
Seite 26
... draw BG equal to EF making an angle ABG equal to DEF , join AG and GC . Because AB and BG are equal to DE and EF , and the contained angle ABG is equal to DEF ; the triangles ABG and DEF ( I. 3. ) are equal , and have equal bases AG and ...
... draw BG equal to EF making an angle ABG equal to DEF , join AG and GC . Because AB and BG are equal to DE and EF , and the contained angle ABG is equal to DEF ; the triangles ABG and DEF ( I. 3. ) are equal , and have equal bases AG and ...
Seite 31
... drawn through the point F pa- rallel to AB , it follows that the converse of the proposition is likewise true , and ... draw , through the point C , a straight line parallel to AB . In AB take any point D , join CD , and at the point C ...
... drawn through the point F pa- rallel to AB , it follows that the converse of the proposition is likewise true , and ... draw , through the point C , a straight line parallel to AB . In AB take any point D , join CD , and at the point C ...
Seite 34
... draw the diagonal AC . Because AB is parallel to CD , the alternate angles CAB and ACD are ( I. 22. ) equal ; and the triangles ABC and ADC , having the side AB equal to CD , AC common to both , and the contained angle CAB equal to ACD ...
... draw the diagonal AC . Because AB is parallel to CD , the alternate angles CAB and ACD are ( I. 22. ) equal ; and the triangles ABC and ADC , having the side AB equal to CD , AC common to both , and the contained angle CAB equal to ACD ...
Andere Ausgaben - Alle anzeigen
Elements of Geometry, and Plane Trigonometry: With an Appendix, and Very ... University Professor Emeritus John Leslie, Sir Keine Leseprobe verfügbar - 2016 |
Häufige Begriffe und Wortgruppen
ABCD adjacent angle altitude angle ABC angle ADB angle BAC base AC bisect centre chord circle circumference consequently construction contained angle cosine decagon denote describe diameter difference distance diverging lines divided draw equal to BC equilateral triangle equivalent to twice evidently exterior angle Geometry given greater half Hence hypotenuse inscribed isosceles triangle join let fall likewise measure parallel perpendicular point G polygon PROB PROP Proposition quadrilateral figure quantities radius ratio rectangle rectangle contained rectilineal figure rhomboid right angles right-angled triangle Scholium segments semicircle semiperimeter side AC sides AB sinB sine square of AB square of AC straight line tangent THEOR tion triangle ABC twice the rectangle twice the square vertex vertical angle whence Wherefore
Beliebte Passagen
Seite 22 - THEOR. Two sides of a triangle are together greater than the third side. The two sides AB and BC of the triangle ABC are together greater than the third side AC. For produce AB until DB be equal to the side BC, and join CD. Because BC is equal to BD, the angle BCD is equal to BDC (I.
Seite 292 - axiom, (If a straight line meets two straight lines, so as to make the two interior angles on the same side of it taken together less than two right angles, these straight lines, being continually produced, will at length meet on that side on which are the angles which are less
Seite 10 - circumference. 35. The diameter of a circle is a straight line drawn through the centre, and terminated both ways by the circumference. It is obvious that all radii of the same circle are equal to each other and to a
Seite 50 - PROB. With a given straight line to construct a rhomboid equivalent to a given rectilineal figure, and having an angle equal to a given angle. Let it be required to construct, with the straight line L, a rhomboid, containing a given space, and having an angle equal to K. Construct (II.
Seite 144 - Proposition is named inverse, or perturbate, equality. PROP. XIX. THEOR. If there be any number of proportionals, as one antecedent is to its consequent, so is the sum of all the antecedents to the sum of all the consequents. .
Seite 236 - &c. &c. PROP. IV. THEOR. The sum of the sines of two arcs is to their difference, as the tangent of half the sum of those arcs to the tangent of half
Seite 110 - Hence a regular twenty-sided figure may be described on a given straight line, by first constructing on it an isosceles triangle having each of the angles at the base double of the vertical angle,
Seite 30 - THEOR. If a straight line fall upon two parallel straight lines, it will make the alternate angles equal, the exterior angle equal to the interior opposite one, and the two interior angles on the same side together equal to two right angles. • Let the straight line EFG fall upon the parallels AB and CD ; the alternate angles AGF and DFG are equal, the
Seite 137 - founded the two following theorems. PROP. VII. THEOR. The terms of an analogy are proportional by inversion, or the second is to the first, as the fourth to the third. Let A : B : : C : D ; then inversely B : A : : D : C.
Seite 88 - THEOR. The angle in a semicircle is a right angle, the angle in a greater segment is acute, and the angle in a smaller segment is obtuse. Let ABD be an angle in a semicircle, or that stands on the semicircumference AED; it is a right angle.