Question #65104

1 Answer
Sep 7, 2017

Yes. Both of them are normed linear spaces which are complete in the sense that every Cauchy sequence in the space converges to a limit point within the space.

However, the norm of a vector in a Banach space is not necessarily defined from the inner product. (Even though inner product is defined on the space)

On the other hand, for any vector #|f># in a Hilbert space #V#, the norm may be defined as,

#||f|| = sqrt (< f|f>)# where #< f|f># denotes an inner product of #|f># (from #V#) with #< f|#
(from the dual space #bar V#).

Thus norms in the Hilbert space are defined using the inner product.

This may not be true for a Banach space.