How to show something is a subspace

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How would you show that {(x,y,z) € R^3 :√11x - √13z=0} is a subspace of R^3?

I know you have to make sure it fits the definition of a subspace, i.e prove
u+v € W
and alpha(v) € W

but I am not sure how you would do this using √11x - √13z=0 ?
 
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HappyN said:
How would you show that {(x,y,z) € R^3 :√11x - √13z=0} is a subspace of R^3?

I know you have to make sure it fits the definition of a subspace, i.e prove
u+v € W
and alpha(v) € W

but I am not sure how you would do this using √11x - √13z=0 ?

What is the definition of addition and scalar multiplication in your vector space?
 
chiro said:
What is the definition of addition and scalar multiplication in your vector space?

Do you mean the 7 axioms?
like: v+w=w+v for all v,w € V
(v+w)+z=v+(w+z) etc?
 
I think that Chiro means think about the axioms and make sure the subspace satisfy them.
In particular check that the sum of two elements in the subspace yield another element in the subspace and that the scalar multiple of an element in the subspace yields another element in the subspace. The rest of the axioms will then follow automatically.
 
Simon_Tyler said:
I think that Chiro means think about the axioms and make sure the subspace satisfy them.
In particular check that the sum of two elements in the subspace yield another element in the subspace and that the scalar multiple of an element in the subspace yields another element in the subspace. The rest of the axioms will then follow automatically.

Yep that's pretty much what I was trying to get the OP to think about.
 
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