a) {(x1,x2,x3) | x1+x2 ≥ 0}(adsbygoogle = window.adsbygoogle || []).push({});

b) {x∈R3 |proj(1,1,1) (x) ∈ Sp({(1,1,1)})}

Prove the set is or is not a subset of R n

I have no idea how to solve this. Our textbook gives NO examples of how to prove these

Please help me get started, a related example would be great too. :)

Thanks- Steve

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# Homework Help: Proof of subspaces

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