|
|
In article
<20051102.1146339208262.JavaMail.jakarta@xxxxxxxxxxxxxxxxxxxxxx>, Cathy
<cathy218@xxxxxxxxx> wrote:
> Hello, all.
> I am doing a problem and have some trouble with it. Any idea is greatly
> appreciated.
> T is a linear operator from normed linear space X to a norm linear space Y.
> I need to prove
> ||T|| = Sup{<Tx,y*>: ||x||<=1,||y*||<=1,x in X, y* in Y*}
>
> It is easy to get ||T||>= Sup<Tx,y*>. But the other direction of the
> inequality troubles me.
>
> Cathy
How about the identity operator, can you do that one?
|
|