Show that the range of the linear operator is not all of R^3

vip_snoopy
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Homework Statement


Show that the range of the linear operator defined by the equations is not all of R3, and find a vector that is not in the range


Homework Equations


w1 = x - 2y + z
w2 = 5x - y + 3z
w3 = 4x + y + 2z


The Attempt at a Solution


can I just show that it does not have an inverse and it's a singular matrix to say it's equivalent to the range is not all or R3?
 
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Yes, but you will still have to find a vector that is not in the range. So just find such a vector and solve both problems at once instead.
 
strange, my edit was not posted.

My question is actually how to find the vector not in the domain?
 
Yes, that is the whole point.

For what values of w1, w2, w3 does
w1 = x - 2y + z
w2 = 5x - y + 3z
w3 = 4x + y + 2z
NOT have a solution.

Just start solving for x, y, and z and see if you run into a problem (probably dividing by 0) for some values of w1, w2, and w3.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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