Proving S is a Subset of T in R³

umzung
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Homework Statement


Show that S ⊆ T, where S and T are both subsets of R^3.

Homework Equations


S = {(1, 2, 1), (1, 1, 2)},
T ={(x,y,3x−y): x,y∈R}

The Attempt at a Solution


I considered finding if S is a spanning set for T but I'm aware that this is perhaps not relevant. If I find {α(1, 2, 1) + β(1, 1, 2): α, β ∈ R}, would this show S to be a subset of T?
 
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Hello Unzung, :welcome:

umzung said:
I'm aware that this is perhaps not relevant
You are right there !

You are done once you have shown that each element of S is also a member of T.
 
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