Is This Set of Triples of Real Numbers a Vector Space?

derryck1234
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Homework Statement



Show whether the set is a vector space: The set of all triples of real numbers (x, y, z) with the operations:

(x, y, z) + (x', y', z') = (x + x', y + y', z + z') and k(x, y, z) = (kx, y, z)

Homework Equations



(10 vector space axioms)

The Attempt at a Solution



I can understand 9 axioms, I just want to confirm that I am doing the right thing on this one:

(m + k)(x, y, z) = ((m+k)x, y, z), which is not equal to k(x, y, z) + m(x, y, z) = (kx, y, z) + (mx, y, z) = ((m+k)x, 2y, 2z).

Is this correct working?

Thanks

Derryck
 
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