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Given that π΄ is a matrix of order two by two, with π one one equal to seven, π one two equal to negative 10, π two one equal to negative nine, and π two two equal to two, find the matrix π΄.
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Weβre told that the matrix π΄ is of order two by two, which means that it has two rows and two columns.
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It therefore has four elements that we need to complete.
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The notation π and then a subscript π and π is used to denote the element in row π and column π of the matrix π΄.
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Weβre told, first of all, that the element π one one is equal to seven.
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This is the element in the first row and first column of the matrix.
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So we can fill in seven in its correct place in the matrix.
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Next, weβre told that π one two is equal to negative 10.
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This is the element in the first row and second column of the matrix π΄.
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So we can fill this element in.
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π two one is equal to negative nine.
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This is the element in the second row and first column of the matrix.
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Finally, we consider the fourth element of the matrix, π two two.
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π two two is the element in the second row and second column of the matrix, which is the only gap that weβve got left to complete.
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The matrix π΄ is the matrix with first row seven, negative 10 and second row negative nine, two.