document.write( "Question 1094593: Prove that there exists a linear transformation T : R2 ! R3 such that T(1; 1) = (1; 0; 2) and
\n" ); document.write( "T(2; 3) = (1;-1; 4): What is T(8; 11)?
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Algebra.Com's Answer #709245 by rothauserc(4718)\"\" \"About 
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Let V = {(1; 1), (2; 3)}
\n" ); document.write( "let U = {(1 0;2), (1; -1; 4)}
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\n" ); document.write( "check if V is a linearly independent or dependent set of vectors
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\n" ); document.write( "write the vectors of V as a matrix with each vector written as a column
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\n" ); document.write( "| 1 2 |
\n" ); document.write( "| 1 3 |
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\n" ); document.write( "transform the matrix to row echelon form
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\n" ); document.write( "r2 - r1 ---> r2
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\n" ); document.write( "| 1 2 |
\n" ); document.write( "| 0 1 |
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\n" ); document.write( "r1 - 2r2 ---> r1
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\n" ); document.write( "| 1 0 |
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\n" ); document.write( "Rank is 2 implies the vectors are linearly independent, furthermore any set of two linearly independent vectors in R2 spans R2. Hence V is a basis for R2.
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\n" ); document.write( "Since V is a basis, there exists only one linear transformation that maps the vectors of V into the vectors of U.
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\n" ); document.write( "To solve this case, multiply the matrix composed by the vectors of U as columns, by the inverse of the matrix composed by the vectors of V as columns.
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\n" ); document.write( "Note that since the vectors of V form a basis for R2, V is invertible.
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\n" ); document.write( "We invert the following matrix
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\n" ); document.write( "| 1 2 |
\n" ); document.write( "| 1 3 |
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\n" ); document.write( "determinant of this matrix = 3 - 2 = 1, and the inverse matrix is
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\n" ); document.write( "| 3 -2 |
\n" ); document.write( "| -1 1 |
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\n" ); document.write( "| 1 1 | times | 3 -2 |
\n" ); document.write( "| 0 -1 | | -1 1 |
\n" ); document.write( "| 2 4 |
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\n" ); document.write( "result is
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\n" ); document.write( "| 2 -1 |
\n" ); document.write( "| 1 -1 |
\n" ); document.write( "| 2 0 |
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\n" ); document.write( "this is our linear transformation T
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\n" ); document.write( "you can check that T maps the given R2 vectors to the vectors in U, you do this by multiplying our T matrix by the vector from V
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\n" ); document.write( "we follow this procedure for (8, 11) and we get
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\n" ); document.write( "(5, -3, 16)
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