Bisectoare si patrulater inscriptibil

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Filip Chindea
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Bisectoare si patrulater inscriptibil

Post by Filip Chindea »

Fie \( A, B, C, D, E \) in plan astfel incat \( ABCD \) este paralelogram iar \( BCED \) este ciclic. Dreapta \( \ell \) prin \( A \) taie segmentul \( [DC] \) si dreapta \( BC \) in punctele \( F, G \) respectiv. Presupunem ca \( EF = EG = EC \). Sa se arate ca \( \ell \) este bisectoarea \( \angle DAB \).

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