Euclid's Elements of geometry, the first three books (the fourth, fifth, and sixth books) tr. from the Lat. To which is added, A compendium of algebra (A compendium of trigonometry).1846 |
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Results 1-5 of 36
Page 10
... absurd : therefore neither of the sides BA nor AC is greater than the other , therefore they are equal . Hence every equiangular triangle is also equilateral ; for whatsoever side is assumed for a base , the angles adjacent to it will ...
... absurd : therefore neither of the sides BA nor AC is greater than the other , therefore they are equal . Hence every equiangular triangle is also equilateral ; for whatsoever side is assumed for a base , the angles adjacent to it will ...
Page 11
... absurd . Therefore the triangles constructed on the same right line cannot have their conterminous sides equal , if the vertex of each fall without the other . F Now let the vertex D of either fall within the other ; and draw CD produce ...
... absurd . Therefore the triangles constructed on the same right line cannot have their conterminous sides equal , if the vertex of each fall without the other . F Now let the vertex D of either fall within the other ; and draw CD produce ...
Page 15
... absurd . Therefore BE is not in the direct line with CB ; and it can be similarly proved that no other line except BD is in the direction of it , therefore BD is a continua- tion of BC . PROPOSITION XV . THEOREM . If two right lines ...
... absurd . Therefore BE is not in the direct line with CB ; and it can be similarly proved that no other line except BD is in the direction of it , therefore BD is a continua- tion of BC . PROPOSITION XV . THEOREM . If two right lines ...
Page 16
... absurd : therefore BA does not fall at the side of the obtuse angle , therefore it falls at the side of the acute angle . COR . 2. Two perpendiculars cannot be drawn from the same point B , to the same right line ED . For , if it be ...
... absurd : therefore BA does not fall at the side of the obtuse angle , therefore it falls at the side of the acute angle . COR . 2. Two perpendiculars cannot be drawn from the same point B , to the same right line ED . For , if it be ...
Page 22
... absurd ; therefore neither of the sides BA and DE is greater than the other ; BA and DE are therefore equal ; but BC and DF are equal ( by Hypoth . ) , and the angles B and D are equal ( by Hypoth . ) , therefore the remaining side AC ...
... absurd ; therefore neither of the sides BA and DE is greater than the other ; BA and DE are therefore equal ; but BC and DF are equal ( by Hypoth . ) , and the angles B and D are equal ( by Hypoth . ) , therefore the remaining side AC ...
Common terms and phrases
absurd AC and CB AC by Prop AC is equal angle ABC angle equal angles by Prop arch bisected centre circumference co-efficient Const construct contained oftener diameter divided divisor double equal angles equal by Constr equal by Hypoth equal by Prop equal right lines equal to AC equal to twice equi-multiples equi-submultiples equiangular equilateral external angle fore fraction given angle given circle given line given right line given triangle greater half a right inscribed less multiplied opposite parallel parallelogram perpendicular PROPOSITION quantities quotient ratio rectangle under AC remaining angles remaining side right angle right line AB right line AC SCHOL segment semicircle side AC similar similarly demonstrated squares of AC submultiple subtract THEOREM tiple touches the circle triangle BAC twice the rectangle twice the square whole
Popular passages
Page 20 - If two triangles have two sides of the one equal to two sides of the...
Page 30 - DE : but equal triangles on the same base and on the same side of it, are between the same parallels ; (i.
Page 209 - ... they have an angle of one equal to an angle of the other and the including sides are proportional; (c) their sides are respectively proportional.
Page 218 - 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 114 - To reduce fractions of different denominators to equivalent fractions having a common denominator. RULE.! Multiply each numerator into all the denominators except its own for a new numerator, and all the denominators together for a common denominator.
Page 90 - 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.
Page 129 - In any proportion, the product of the means is equal to the product of the extremes.
Page 163 - Magnitudes are said to be in the same ratio, the first to the second and the third to the fourth, when, if any equimultiples whatever be taken of the first and third, and any equimultiples whatever of the second and fourth, the former equimultiples alike exceed, are alike equal to, or alike fall short of, the latter equimultiples respectively taken in corresponding order.
Page 215 - ... are to one another in the duplicate ratio of their homologous sides.
Page 160 - PROPOSITION XV. PROBLEM. To inscribe an equilateral and equiangular hexagon in a given circle. Let ABCDEF be the given circle.