The Elements of EuclidDesilver, Thomas, 1838 - 416 páginas |
Dentro del libro
Resultados 1-5 de 100
Página 6
... angles is called a right angle : and the straight line which stands on the other is called a perpendicular to it . XI . An obtuse angle is that which is greater than a right angle . XII . An acute angle is that which is less than a ...
... angles is called a right angle : and the straight line which stands on the other is called a perpendicular to it . XI . An obtuse angle is that which is greater than a right angle . XII . An acute angle is that which is less than a ...
Página 7
... right - angled triangle , is that which has a right angle . XXVIII . An obtuse - angled triangle , is that which has an obtuse angle . XXIX . An acute - angled triangle , is that which has three acute angles . XXX . Of four - sided ...
... right - angled triangle , is that which has a right angle . XXVIII . An obtuse - angled triangle , is that which has an obtuse angle . XXIX . An acute - angled triangle , is that which has three acute angles . XXX . Of four - sided ...
Página 8
... right angles , but has not all its sides equal . XXXII . A rhombus is that which has its sides equal , but its angles are not right angles . оо XXXIII . A rhomboid , is that which has its opposite sides equal to one another , but all ...
... right angles , but has not all its sides equal . XXXII . A rhombus is that which has its sides equal , but its angles are not right angles . оо XXXIII . A rhomboid , is that which has its opposite sides equal to one another , but all ...
Página 9
... right angles are equal to one another . XII . " If a straight line meet 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 ...
... right angles are equal to one another . XII . " If a straight line meet 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 ...
Página 16
... right angles to a given straight line , from a given point in the same . F Let AB be a given straight line , and C a point given in it : it is re- quired to draw a straight line from the point C at right angles to AB . * Take any point ...
... right angles to a given straight line , from a given point in the same . F Let AB be a given straight line , and C a point given in it : it is re- quired to draw a straight line from the point C at right angles to AB . * Take any point ...
Otras ediciones - Ver todas
Términos y frases comunes
altitude angle ABC angle BAC base BC BC is equal BC is given bisected centre circle ABCD circumference cone cylinder demonstrated described diameter draw drawn equal angles equiangular equimultiples Euclid ex æquali excess fore given angle given in magnitude given in position given in species given magnitude given ratio given straight line gles gnomon greater join less Let ABC multiple parallel parallelogram parallelogram AC perpendicular point F polygon prism proportionals proposition pyramid Q. E. D. PROP radius ratio of AE rectangle CB rectangle contained rectilineal figure remaining angle right angles segment sides BA similar sine solid angle solid parallelopiped square of AC square of BC straight line AB straight line BC tangent THEOR triangle ABC triplicate ratio vertex wherefore
Pasajes populares
Página 34 - 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. Let the straight line AB be divided into any two parts at the point C : the squares of AB, BC shall be equal to twice the rectangle AB, BC, together with the square of AC.
Página 143 - Wherefore, in equal circles &c. QED PROPOSITION B. THEOREM If the vertical angle of a triangle be bisected by a straight line which likewise cuts the base, the rectangle contained by the sides of the triangle is equal to the rectangle contained by the segments of the base, together with the square on the straight line which bisects the angle.
Página 63 - The angle in a semicircle is a right angle; the angle in a segment greater than a semicircle is less than a right angle; and the angle in a segment less than a semicircle is greater than a right angle.
Página 246 - 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 9 - If one side of a triangle be produced, the exterior angle is greater than either of the interior opposite angles.
Página 119 - If two triangles have one angle of the one equal to one angle of the other and the sides about these equal angles proportional, the triangles are similar.
Página 19 - All the interior angles of any rectilineal figure, together with four right angles, are equal to twice as many right angles as the figure has sides.
Página 12 - To construct a triangle of which the sides shall be equal to three given straight lines ; but any two whatever of these lines must be greater than the third (20.
Página 78 - If two triangles have two angles of the one equal to two angles of the other, each to each, and one side equal to one side, viz. either the sides adjacent to the equal...
Página 131 - ... rectilineal figures are to one another in the duplicate ratio of their homologous sides.