Recent content by negation

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    Show that non-zeros rows in REF are linearly independent

    Alright I was sloppy and careless with words. The matrix has entries aaa, abb ...ann and has zeroes everywhere else.
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    Set of vectors whose coordinates are integer (is a subspace?)

    I admit it was sloppy use of words. The correct word would be 'element'. It's fuzzy to me as to why the vector (1,1,1) was chosen. Could we have chosen (2,2,2)?
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    Show that non-zeros rows in REF are linearly independent

    Let's stick to " For a matrix in REF, the non-zero row with the entry aaa is to the left of the non-zero row with the entry abb to the left of entry acc to the left of add and so on to ann"
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    Set of vectors whose coordinates are integer (is a subspace?)

    Yea it is. It's probably shaky understanding of the concept and not employing the appropriate terminology.
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    Show that non-zeros rows in REF are linearly independent

    For a matrix in REF, the non-zero row with the entry aaa is to the left of the non-zero row with the entry abb to the left of entry acc to the left of add and so on to ann Tell me if there's a better way of sub-scripting the entries. Edit: I could have been confused by your question. a3ij is...
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    Show that non-zeros rows in REF are linearly independent

    For a matrix in REF, the non-zero row with the entry aij is to the left of the non-zero row with the entry a2ij to the left of entry a3ijto the left of a4ij and so on to anij.
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    Show that non-zeros rows in REF are linearly independent

    Homework Statement Given 2 1 1 0 0 0 1 1 0 0 0 3(i) Show that the rows of A are linearly independent. (ii) Show that the nonzero rows of any matrix in row echelon form are linearly independent.The Attempt at a Solution i) REF gives 1 0 0 | 0 0 1 0 | 0 0 0 1 | 0 0 0 0 | 0 x1 = x2 = x3 =x4 =...
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    Is This Set a Spanning Set for R3?

    With respect to the question, the solution set has 1 free variable. Thus, the solution set has infinitely many solutions. And so, span {(1; 1; 0);(0; 0; 2);(0; 0; 1);(1; 2; 3)} is a spanning set for R4. Keeping this in mind, I could have equally, instead of expressing [a;b;c;d] as a linear...
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    Explanation of solution to given question (subspace)

    I should have known not to complicate the answer by setting 1/k = y. But I have this one. If k = 1, we have 1(1-1) | (-1+1) and this produces 0 = 0. We have an infinite solution set. 0x3 = 0 setting x3 = y we see that via back substituition x2 = 1-2y x1 = [2+2(1-2y)]/-4 :-p (lazy...
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    Set of vectors whose coordinates are integer (is a subspace?)

    I'm unsure if I understood the question rightly. There would hardly be any substance in my workings if my understanding of the question is misguided. I assume the question is asking me to construct a vector whose coordinates are element of integers and subject them to the the condition of...
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    Explanation of solution to given question (subspace)

    It is clear now. I was earlier able to work to the part where k(1-k)x3 = (-k+1) simplifying produces x3 = 1/k but was confused as to what I should do with what I had especially since it conflicted with what my answer key showed. In response to your question, x3 = 1/k. If x3 = y, 1/k = y. ∴ x3...
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    Is This Set a Spanning Set for R3?

    Homework Statement Is {(1; 1; 0);(0; 0; 2);(0; 0; 1);(1; 2; 3)} a spanning set for R3The Attempt at a SolutionThis is supposed to be easy but the answer sheet might be wrong. The answer I have says it is and then proceed to say that (0;0;2) is linearly independent. But it isn't because...
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    Set of vectors whose coordinates are integer (is a subspace?)

    Homework Statement For a set of vectors in R3, is the set of vectors all of whose coordinates are integers a subspace?The Attempt at a Solution I do not exactly understand if I should be looking for a violation or a universal proof. If x,y, z \in Z then x,y,z can be writted as...
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    Explanation of solution to given question (subspace)

    I'm still not capturing the full essence of part (1). Maybe some simple examples? part(3): if k ≠ 1 and k ≠ 0 then we can pick any values of k? But what is the corollary from this?
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    Explanation of solution to given question (subspace)

    Homework Statement -4x1 +2x2 =2 4x1 -3x2 -2x3 =-3 2x1 -x2 +(k - k2)x3 =-k Find the values of k for which the system has 1) unique solution, 2) infinitely many solution and 3) no solution The Attempt at a Solution In REF: the matrix is -4 2 0 | 2 0 -1 -2 | -1 0 0 k(1-k)...