Lin Alg - Find the basis and dimension

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    Basis Dimension
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Find the basis and dimension of the following homogeneous system:
Code:
A =     |1 0 2| |x1|
        |2 1 3| |x2| = [0,0,0]
        |3 1 2| |x3|
My attempt:

Solving the coefficient matrix for RREF, I get the identify matrix.
So, x1=x2=x3=0 and the only solution is a trivial one.

Does that mean there is no basis(empty basis), or that the basis only contains the zero vector and has dimension zero?
 
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The dimension is equal to the number of vectors in a basis, so if the solution space is zero-dimensional, the basis is empty.
 
vela said:
The dimension is equal to the number of vectors in a basis, so if the solution space is zero-dimensional, the basis is empty.


Thanks for the help!
 
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