i need to show that the unitary maps form a group under multiplication. ive never had algebra (im in linear algebra) so this is the first time ive seen this idea of 'groups'. i tried to look stuff up, so i think i see now that i need to show: 1) identity is an element 2) if x,y are elements of the group then the product xy is in the group 3) if x is an element, then its inverse is in the group.(adsbygoogle = window.adsbygoogle || []).push({});

I'm not really sure how to show these things since I'm new to this. All I really have to work with is that a unitary mapping M satisfies ll Mx - My ll = ll x - y ll for all x,y.

Can you help me get started? Thanks, Sarah :)

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# Homework Help: Algebra: unitary mappings

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