Is the vector x unique in the context of linear algebra?

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SUMMARY

The vector x defined as x = (-15, -3, 0) + x_3(10, 0, 1) is not unique due to the presence of the free variable x_3, which allows for multiple solutions. The components of x can be expressed as x_1 = -15 + 10t, x_2 = -3, and x_3 = t, where t is any real number. The discussion clarifies that the uniqueness of vector x is contingent upon the constraints placed on the variable x_3. If x_3 is allowed to vary freely, then x is not unique.

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Homework Statement


Determine if the vector x is unique.

x = (-15, -3, 0) + x_3 (10, 0, 1)

Note: The scalars should be vertically placed instead of horizontal.

The Attempt at a Solution



Seeing that there is a free variable, I said that x is not unique, but my teacher marked it wrong. Why is it unique, and in what case would it not be unique?
 
Last edited:
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So, x_3 is the 3rd component of x correct? If that's the case (I don't see what else it could be) then I agree that it doesn't seem to be unique as we have

(1) x_1 = -15 + 10t
(2) x_2 = -3
(3) x_3 = t

Now t can be chosen to be any real number. Are you sure that you copied them correctly?
 
Last edited:

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