Let S be a finite set of real numbers. What is a natural inner product to define on the space of all functions f:S->R? I want to approximate an arbitrary function with a polynomial of a fixed degree (both of which are defined only on S), and I want to use projections to do it, but I have no inner product.(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Inner Product

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