Elements of Geometry: Containing the First Six Books of Euclid, with a Supplement on the Quadrature of the Circle, and the Geometry of Solids ; to which are Added, Elements of Plane and Spherical Trigonometry |
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Page 46
... similar construction which reduces two of them to one , will reduce three of them to two , and these two to one , and so of others . PROP . I. PROB . To find the side of a square equivalent to the difference of two given squares . Draw ...
... similar construction which reduces two of them to one , will reduce three of them to two , and these two to one , and so of others . PROP . I. PROB . To find the side of a square equivalent to the difference of two given squares . Draw ...
Page 62
... Similar segments of a circle , are those in which the angles are equal , or which contain equal an- gles . PROP . I. PROB . To find the centre of a given circle . Let ABC be the given circle ; it is required to find its centre . Draw ...
... Similar segments of a circle , are those in which the angles are equal , or which contain equal an- gles . PROP . I. PROB . To find the centre of a given circle . Let ABC be the given circle ; it is required to find its centre . Draw ...
Page 76
... similar to the segment ADB , and similar segments of circles contain ( 9. def . 3. ) equal angles , the angle ACB is equal to the angle ADB , the exterior to the interior , which is impossible ( 16. 1. ) . PROP . XXIV . THEOR . A B Similar ...
... similar to the segment ADB , and similar segments of circles contain ( 9. def . 3. ) equal angles , the angle ACB is equal to the angle ADB , the exterior to the interior , which is impossible ( 16. 1. ) . PROP . XXIV . THEOR . A B Similar ...
Page 78
... similar ( 9. def . 3. ) to the segment EDF ; and they are upon equal straight lines BC , EF ; but similar segments of circles upon equal straight lines are equal ( 24. 3. ) to one another , therefore the segment BAC is equal to the ...
... similar ( 9. def . 3. ) to the segment EDF ; and they are upon equal straight lines BC , EF ; but similar segments of circles upon equal straight lines are equal ( 24. 3. ) to one another , therefore the segment BAC is equal to the ...
Page 87
... similar reasons FB , FC , are equal ; hence the points A , B , C , are all equally distant from the point F , and consequently lie in the circumference of the circle , whose centre is F , and radius FA . It is obvious , that besides ...
... similar reasons FB , FC , are equal ; hence the points A , B , C , are all equally distant from the point F , and consequently lie in the circumference of the circle , whose centre is F , and radius FA . It is obvious , that besides ...
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Common terms and phrases
ABC is equal ABCD adjacent angles altitude angle ABC angle ACB angle BAC base BC bisected centre chord circle ABC circumference cosine cylinder demonstrated described diameter divided draw equal and similar equal angles equiangular equilateral equilateral polygon equimultiples Euclid exterior angle fore four right angles given rectilineal given straight line greater Hence hypotenuse inscribed join less Let ABC magnitudes meet multiple opposite angle parallel parallelogram parallelopiped perpendicular plane polygon prism PROB PROP proportional proposition quadrilateral radius ratio rectangle contained rectilineal figure remaining angle right angled triangle SCHOLIUM segment semicircle shewn side BC sine solid angle solid parallelopiped spherical angle spherical triangle square straight line BC THEOR third touches the circle triangle ABC triangle DEF wherefore
Popular passages
Page 49 - If a straight line be divided into two equal parts, and also into two unequal parts; the rectangle contained by the unequal parts, together with the square of the line between the points of section, is equal to the square of half the line.
Page 147 - ... 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.
Page 292 - 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.
Page 7 - 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.
Page 139 - K hag to M the ratio which is compounded of the ratios of the sides ; therefore also the parallelogram AC has to the parallelogram CF the ratio which is compounded of the ratios of the sides. COR. Hence, any two rectangles are to each other as the products of their bases multiplied by their altitudes.
Page 33 - Parallelograms upon the same base and between the same parallels, are equal to one another.
Page 79 - If a straight line touch a circle, and from the point of contact a straight line be drawn cutting the circle, the angles made by...
Page 125 - 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.
Page 131 - 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 78 - 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.