What is the basis and dimension of a subspace given by (1,-2,3,-1), (1,1,-2,3)?

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The discussion focuses on determining the basis and dimension of a subspace W in R generated by the vectors (1,-2,3,-1) and (1,1,-2,3). It is established that these vectors can serve as a basis if they are linearly independent, which can be verified through a dependence check. If the vectors are independent, they form a basis, resulting in a dimension of 2; if dependent, one vector would suffice, leading to a dimension of 1. The participants agree that simplifying the vectors into row-echelon form would not alter their status as a basis. Ultimately, the dimension of the subspace is defined by the number of vectors in the spanning set.
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say we are given a subspace like this:

Being W the subspace of R generated by (1,-2,3,-1), (1,1,-2,3) determine a basis and the dimension of the subspace.

Won't the vectors given work as a basis, as long as they are linearly independent?
If so, all we have to do is check for dependance, and if the system is dependent, we would choose one of the vectors as a base, and the dimension would be 1. if it was independent, the basis would be both of those vectors, and the dimension would be 2.

By the same logic, If I was asked to determine the dimension of the subspace generated by those vectors, i'd just check for linear dependance.
Is this right?

By the way, should I simplify the basis by putting them in a matrix and getting it to row-echelon form? would the basis still "work" after that?
 
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The two vectors are obviously linearly independent; if they were dependent, one would be a constant multiple of the other. If you had been given three vectors, you wouldn't be able to tell by inspection that the three vectors were linearly independent.

Since the two vectors give generate the subspace in question, they span the subspace, and hence form a basis for it.

The dimension of a vector subspace is equal to the number of vectors in the spanning set for the subspace.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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