document.write( "Question 200482: Hi everyone I asked a similiar question recently but got no responce, I may have input the question incorrectly.
\n" ); document.write( "I need to solve the following Matrices and comment on the outcomes.
\n" ); document.write( "For the following:
\n" ); document.write( "A =
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\n" ); document.write( "\n" ); document.write( "B =
\n" ); document.write( "( 1 -1 )
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\n" ); document.write( "\n" ); document.write( "C =
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\n" ); document.write( "Find and state why or why not the following is possible.
\n" ); document.write( "i) A^T + C
\n" ); document.write( "ii) AB
\n" ); document.write( "iii) CB
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Algebra.Com's Answer #150764 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"A=%28matrix%282%2C3%2C2%2C-1%2C1%2C1%2C1%2C-2%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"B=%28matrix%282%2C2%2C1%2C-1%2C2%2C3%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"C=%28matrix%283%2C2%2C1%2C-1%2C0%2C1%2C-2%2C1%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "i)\r
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\n" ); document.write( "\n" ); document.write( "Step 1: Find the transpose of A to get \"A%5ET\"\r
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\n" ); document.write( "\n" ); document.write( "Step 2: Add \"A%5ET\" to C (just add up each component) to get\r
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\n" ); document.write( "\n" ); document.write( "\"A%5ET%2BC=%28matrix%283%2C2%2C3%2C0%2C-1%2C2%2C-1%2C-1%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So \"A%5ET%2BC=%28matrix%283%2C2%2C3%2C0%2C-1%2C2%2C-1%2C-1%29%29\"\r
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\r
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\n" ); document.write( "\n" ); document.write( "ii) The product AB is NOT possible since the dimensions of A are 2x3 and the dimensions of B are 2x2. The inner dimensions MUST match for matrix multiplication to be defined.\r
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\n" ); document.write( "\n" ); document.write( "So \"AB\" does not exist.\r
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\n" ); document.write( "\n" ); document.write( "iii)\r
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\n" ); document.write( "\n" ); document.write( "Since the first matrix is a 3 by 2 matrix and the second matrix is a 2 by 2 matrix, this means that the resulting matrix will be a 3 by 2 matrix.\r
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\n" ); document.write( "\n" ); document.write( "So the final resulting matrix will look like:\r
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\n" ); document.write( "\n" ); document.write( "\"CB=%28matrix%283%2C2%2Cx%2Cx%2Cx%2Cx%2Cx%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "note: the \"x\"s are just placeholders for now\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 1st row of the first matrix by the 1st column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "1st row, 1st column: \r
\n" ); document.write( "\n" ); document.write( "\"%281%29%2A%281%29%2B%28-1%29%2A%282%29=1%2B-2=-1\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 1st row, 1st column of the resulting matrix is \"-1\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"CB=%28matrix%283%2C2%2C-1%2Cx%2Cx%2Cx%2Cx%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 1st row of the first matrix by the 2nd column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "1st row, 2nd column: \r
\n" ); document.write( "\n" ); document.write( "\"%281%29%2A%28-1%29%2B%28-1%29%2A%283%29=-1%2B-3=-4\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 1st row, 2nd column of the resulting matrix is \"-4\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"CB=%28matrix%283%2C2%2C-1%2C-4%2Cx%2Cx%2Cx%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 2nd row of the first matrix by the 1st column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "2nd row, 1st column: \r
\n" ); document.write( "\n" ); document.write( "\"%280%29%2A%281%29%2B%281%29%2A%282%29=0%2B2=2\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 2nd row, 1st column of the resulting matrix is \"2\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"CB=%28matrix%283%2C2%2C-1%2C-4%2C2%2Cx%2Cx%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 2nd row of the first matrix by the 2nd column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "2nd row, 2nd column: \r
\n" ); document.write( "\n" ); document.write( "\"%280%29%2A%28-1%29%2B%281%29%2A%283%29=0%2B3=3\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 2nd row, 2nd column of the resulting matrix is \"3\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"CB=%28matrix%283%2C2%2C-1%2C-4%2C2%2C3%2Cx%2Cx%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 3rd row of the first matrix by the 1st column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "3rd row, 1st column: \r
\n" ); document.write( "\n" ); document.write( "\"%28-2%29%2A%281%29%2B%281%29%2A%282%29=-2%2B2=0\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 3rd row, 1st column of the resulting matrix is \"0\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"CB=%28matrix%283%2C2%2C-1%2C-4%2C2%2C3%2C0%2Cx%29%29\"\r
\n" ); document.write( "\n" ); document.write( "--------------------------------------------------\r
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\n" ); document.write( "\n" ); document.write( "Multiply the corresponding entries from the 3rd row of the first matrix by the 2nd column of the second matrix. After multiplying, add the values:\r
\n" ); document.write( "\n" ); document.write( "3rd row, 2nd column: \r
\n" ); document.write( "\n" ); document.write( "\"%28-2%29%2A%28-1%29%2B%281%29%2A%283%29=2%2B3=5\"\r
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\n" ); document.write( "\n" ); document.write( " So the element in the 3rd row, 2nd column of the resulting matrix is \"5\". Now let's update the matrix:\r
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\n" ); document.write( "\n" ); document.write( "\"CB=%28matrix%283%2C2%2C-1%2C-4%2C2%2C3%2C0%2C5%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So \r
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\n" ); document.write( "\n" ); document.write( "In other words, \"CB=%28matrix%283%2C2%2C-1%2C-4%2C2%2C3%2C0%2C5%29%29\"\r
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