Publi es en 1907, ces le ons de Jacques Hadamard et Maurice Fr chet font autorit dans leur domain. Elles couvrent la th orie des variations et ses applications sur le premier ordre et le secondordre ainsi quesur la th orie de Jacobi. This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work is in the "public domain in the United States of America,...