How do I determine if a set is a subspace?

[Shackleford]

I'm not sure how to tackle #6.

I want to make sure my logic about the rest is correct. There's still a little fuzziness on how to show something is a subspace. I know it has to have the zero vector and be closed under scalar multiplication and addition.

 

[HallsofIvy]

What is your question? Problem 6, for example, tells you do do a specific thing. Have you done it?

 

[Shackleford]

What is your question? Problem 6, for example, tells you do do a specific thing. Have you done it?

I'm not sure how to tackle #6.

I want to make sure my logic about the rest is correct. There's still a little fuzziness on how to show something is a subspace. I know it has to have the zero vector and be closed under scalar multiplication and addition.

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