2. Formulations Faibles

This is the problem of all great revelations: their significance so often exceeds the frame of our comprehension. We understand only after, always after. Not simply when it is too late, but precisely because it is too late.

—R. Scott Bakker - The Darkness That Comes Before: Book 1 of the Prince of Nothing (Titre français : Autrefois, les Ténèbres),

• 2.1. Espaces de Hilbert : rappels
• 2.2. Formulation Faible
• 2.3. Théorème de Lax-Milgram
• 2.4. Espaces de Sobolev
• 2.5. Application au problème modèle