- #1
nayfie
- 50
- 0
Homework Statement
Is the following a subspace of [itex]R^{n}[/itex] for some n?
[itex]W = {(x, y, z) \in R^{3} | 2x - y = 3z + x = 0}[/itex]
Homework Equations
A subspace of [itex]R^{n}[/itex] is a subset [itex]W[/itex] of [itex]R^{n}[/itex] such that;
1. [itex]0 \in W[/itex]
2. [itex]\forall u, v \in W; u + v \in W[/itex]
3. [itex]\forall c \in R[/itex] and [itex]u \in W[/itex]; [itex]cu \in W[/itex]
The Attempt at a Solution
I have checked that the zero vector is contained in the subset, by first letting x = 0.
2x - y = 0, therefore if x = 0, y is also equal to 0.
3z + x = 0, so if x = 0, z is also equal to 0.
The problem here is that now I have no idea how to prove that W is closed under addition and scalar multiplication.
Any help would be greatly appreciated! :)