Possible Duplicates:
Norms Induced by Inner Products
From norm to scalar product
Given a normed space $(X, \|\cdot\|)$. Is it possible to define an inner product $\langle \cdot, \cdot \rangle$ on space $X$ based on the norm $\|\cdot\|$?
Possible Duplicates:
Norms Induced by Inner Products
From norm to scalar product
Given a normed space $(X, \|\cdot\|)$. Is it possible to define an inner product $\langle \cdot, \cdot \rangle$ on space $X$ based on the norm $\|\cdot\|$?