| René Descartes - Philosophy - 1988 - 276 pages
...cannot divide it, at least in our thought). And because of these facts it can be truly asserted that **the three angles of every triangle are equal to two right angles** and that every body is divisible. Fifthly, I ask my readers to spend a great deal of time and effort... | |
| 268 pages
...a quadrilateral have two of its opposite sides parallel, and the two others equal but not parallel, **any two of its opposite angles are together equal to two right angles.** In quad. ABCD let AD || BC and AB = DC. AD is not equal to BC, for then AB would be both equal to and... | |
| University of Cambridge - 1844 - 550 pages
...quadrilateral be inscribable in two ellipses whose major axes are parallel or perpendicular to one another, **any two of its opposite angles are together equal to two right angles.** 4. A weight is supported by two pistons which are rigidly connected together, and which work in two... | |
| 564 pages
...We wish to recall that proposition. Arbitrary association of ideas immediately suggests the words, **'The three angles of every triangle are equal to two right angles.'** But at first these are words only : our mind runs along an established train of sounds. By well-formed,... | |
| Electronic journals - 1900 - 370 pages
...good only under the presupposition, that the constant is infinitely great. Only then is it true, that **the three angles of every triangle are equal to two right angles** ; also this can be easily proven if one takes as given the proposition, that the constant is infinitely... | |
| 1927 - 588 pages
...certainty. In mathematical reasoning our knowledge is greater than our ignorance. When, you have proved that **the three angles of every triangle are equal to two right angles** , there is an end of doubt; because there are no materials for ignorance to work up into phantoms;... | |
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