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azdang
Mar12-09, 02:06 PM
1. The problem statement, all variables and given/known data
X is the space of ordered n-tuples of real numbers and ||x||=max|\xij| where x=(\xi1,...,\xin). What is the corresponding norm on the dual space X'?


2. Relevant equations



3. The attempt at a solution
I think the answer is that ||x*||=|x_1|+...+|x_n| , but I'm not sure if that's correct or how to show it. Any ideas? Thanks so much.

matt grime
Mar12-09, 02:15 PM
What is the definition of the dual space and its norm?

azdang
Mar12-09, 02:25 PM
Well, I know the dual space,X', is the set of all bounded linear functionals on X and the norm on that space is:
||f||=sup|f(x)|/||x|| for x in X and x not equal to 0
or
||f||=sup|f(x)| for x in X and ||x||=1

azdang
Mar14-09, 02:45 PM
Hey guys, although Matt advised me to think about the definitions, I'm still confused how to apply them to this problem. Any ideas? Thanks so much.