Let (V ; <,>) be a Euclidean space and let x, y and z be nonzero vectors of V . Prove that:
They tell us that we must use the Schwarz inequality in the particular case of the usual Euclidean space R^3:
Therefore, it is a question of conveniently choosing ?1, ?2, ?3 and ?1, ?2, ?3 so that, Using the previous inequality, we arrive at, or at least get very close to, the inequality proposed in the statement. The cyclical nature of the sums must be taken into account.
They tell us that we must use the Schwarz inequality in the particular case of the usual Euclidean space R^3:
Therefore, it is a question of conveniently choosing ?1, ?2, ?3 and ?1, ?2, ?3 so that, Using the previous inequality, we arrive at, or at least get very close to, the inequality proposed in the statement. The cyclical nature of the sums must be taken into account.