document.write( "Question 15127: A^T denotes the transpose of a matrix A.
\n" ); document.write( "Show that = Tr(B^T,A) defines an inner product on R^(n x n)\r
\n" ); document.write( "\n" ); document.write( "Let U be the set of symmetric 2 x 2 matrices with real entries. U is subspace of R (2x2). Find an orthonormal basis of U with respect to the above inner product.
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Algebra.Com's Answer #7533 by khwang(438)\"\" \"About 
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A : nxn square matrix over R. (missing)
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\n" ); document.write( "A^T denotes the transpose of a matrix A.
\n" ); document.write( "Show that = Tr(B^T,A) defines an inner product on \"R%5E%28n+x+n%29+\"
\n" ); document.write( "Let U be the set of symmetric 2 x 2 matrices with real entries. U is subspace of R (2x2). Find an orthonormal basis of U with respect to the above inner product.\r
\n" ); document.write( "\n" ); document.write( " Let A = (aij), B = (bij) be nxn sq. matrices over R. (\"SIGMA\" means summation)
\n" ); document.write( " Define (A,B) = \"Tr%28B%5E%28T%29+A%29+\"= \"+SIGMA+\"\"SIGMA\" \"+b%5Bki%5D+a%5Bki%5D+\"(k=1,2..,n)(i=1,2..,n)
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\n" ); document.write( " You have to check the definition of inner product (as symmetric
\n" ); document.write( " , linear, positive definite, all very easy)
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\n" ); document.write( " Note the dim of the vector space \"R%5E%282x2%29\" = 4.
\n" ); document.write( " And dim U = 3 (why?)
\n" ); document.write( " Let A=
\n" ); document.write( " (1 0)
\n" ); document.write( " (0 0)
\n" ); document.write( " B=
\n" ); document.write( " (0 0)
\n" ); document.write( " (0 1)
\n" ); document.write( " C =
\n" ); document.write( " (0 \"1%2Fsqrt%282%29+\" )
\n" ); document.write( " (\"1%2Fsqrt%282%29\" 0)
\n" ); document.write( " then {A,B,C} forms an o.n. basis of U.\r
\n" ); document.write( "\n" ); document.write( " You should test (A,A)=(B,B)=(C,C)= 1.
\n" ); document.write( " (A,B) = (B,C) =(C,A) = 0\r
\n" ); document.write( "\n" ); document.write( " Kenny
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