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Finding a matrix from a formula for each entry, which involves the row and column numbers of that entry. Not randomized because it's the same as in our workbook. But the variables are made in a way that it should be easy to randomise the size of the matrix, and the to change the formula for the input in not too many places.

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(This question is not randomised. You can find a version with randomised matrix size, see link in Workbook.)

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Find the \\(\\var{m}\\times \\var{n}\\) matrix \\(A=(a_{ij})_{\\var{m}\\times \\var{n}}\\) whose entries satisfy the stated condition:

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The entry \\(a_{ij}\\) is the entry in row \\(i\\) and column \\(j\\). So when we know the row and column, we can work out the entry from the formula.

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a) \\(a_{ij}=i+j\\), so \\(a_{11}=1+1=2\\) and \\(a_{12}=1+2=3\\) and so on.

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\\[ A = \\var{generalA} =\\var{unresolvedA1}= \\var{A1}\\]

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b) \\(a_{ij}=i^{j-1}\\), so \\(a_{11}=1^{0}=1\\) and \\(a_{22}=2^{1}=2\\) and so on.

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\\[ A = \\var{generalA} =\\var{unresolvedA2}= \\var{A2}\\]

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matrix([2,3,4,5],[3,4,5,6],[4,5,6,7],[5,6,7,8])

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matrix([1,1,1,1],[1,2,4,8],[1,3,9,27],[1,4,16,64])

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latex('\\\\begin{pmatrix} 1+1&1+2 &1+3 & 1+4\\\\\\\\ 2+1 & 2+2 & 2+3 & 2+4 \\\\\\\\ 3+1 & 3+2 & 3+3 & 3+4 \\\\\\\\ 4+1 & 4+2 & 4+3 & 4+4\\\\end{pmatrix}')

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['&','&','&','\\\\\\\\']

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number of columns

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number of rows

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\\(a_{ij}=i+j\\). Then \\(A= \\) [[0]]

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\\(a_{ij}=i^{j-1}\\). Then \\(A= \\) [[0]]

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