Tuesday, September 12, 2017

linear algebra - Vector space of real vectors over field complex scalars.




Let V={(a1,a2,,an):aiR  for i=1,2,,n}; So V is a vector space over R. Is V a vector space over the field of complex numbers with the operations of coordinatewise addition and multiplication?



I don't need an actual answer for this, as I just want to confirm that I understand what the question is asking. Paraphrasing: If V=Rn and F=R, then we know that V is a vector space. If F=C, then is V still a vector space (Is the set of real vectors vRn over the field of complex scalars a vector space)?


Answer



One of the axioms of a vector space is that λvV for all λF and vV.



Let V=R and F=C. If v=1 and λ=i then λv=i and that does not belong to R.



In such a case, the pair (R,F) fails to be closed under scalar multiplication.


No comments:

Post a Comment

analysis - Injection, making bijection

I have injection f:AB and I want to get bijection. Can I just resting codomain to f(A)? I know that every function i...