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#1 2013-02-25 04:13:58
- 123ronnie321
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Vector Spaces!
Let V be a vector space and A,B be subsets of V .
prove that: span (A U B) = span (A) + span (B)
looks pretty obvious but dont know how to prove it using math
#2 2013-02-26 17:11:54
- anonimnystefy
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Re: Vector Spaces!
Hi 123ronnie321
I don't think that's true. Look at A={(1,0,0),(0,1,0)} and B={(1,0,0),(0,0,1)}, for example.
Last edited by anonimnystefy (2013-02-26 17:14:28)
The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón
#3 2013-02-27 01:17:52
- scientia
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Re: Vector Spaces!
I think 123ronnie321 is looking for – the direct sum, not the union.
#4 2013-02-27 05:22:24
- anonimnystefy
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Re: Vector Spaces!
Ah, I am sorry, then.
The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón