 | Isaac Todhunter - Euclid's Elements - 1880 - 426 pages
...must be greater than a right angle. [I. 13. But the angle AGB was shewn to be equal to the angle &iF; therefore the angle at F is greater than a right angle. But the angle at Fii leas than a right angle; [Hypothesis. which is absurd. Therefore the angles ABC and... | |
 | Euclid, Isaac Todhunter - Euclid's Elements - 1883 - 428 pages
...the adjacent angle AGB must be greater than a right angle. [I. 13. But the angle AGB was shewn to be equal to the angle at F; therefore the angle at F is greater than a right angle. But the angle at F is less than a right angle ; [Hypothesis. which is absurd. Therefore the angles ABC... | |
 | Euclid - 452 pages
...angle ; so that the angle AGB adjacent to it is greater than a right angle. [i. 13] And it was proved equal to the angle at F; therefore the angle at F is also greater than a right angle. But it is by hypothesis less than a right angle : which is absurd.... | |
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But it was proved that the angle AGB is equal to the angle at F ; therefore the angle at F is greater than a right angle : But by the hypothesis, it is less than a right angle ; which is absurd. 
