document.write( "Question 29838: I dont understand these Partician Matrices and how to break it up.\r
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document.write( "Compute the following matrix
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document.write( "1 0 0 0
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document.write( "0 1 0 0
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document.write( "0 1 1 0
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document.write( "0 -1 0 1 \r
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document.write( "The entire matrix is to the exponent 2006\r
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document.write( "Thank you so much! \n" );
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Algebra.Com's Answer #16590 by khwang(438) ![]() You can put this solution on YOUR website! Some facts that you have to know: \n" ); document.write( " 1) The Caley Hamilton Theorem: \n" ); document.write( " If f(x) is the characteristic polynomial for a given matrix A, \n" ); document.write( " then f(A)= 0. [Note deg of f(x) = size A = n) \n" ); document.write( " Now A is 4 x4 matrix, deg char poly of A = 4, so any high power \n" ); document.write( " of A can be reduced to at most of exponeent 3 by division.\r \n" ); document.write( "\n" ); document.write( " 2) To find the minnimal polynomial m(x) for A, i.e. the lowest \n" ); document.write( " deg (real heer)poy. such that m(A)= 0. Also, m(x) must divide \n" ); document.write( " char for A and contains all eigenvalues for A as roots. \n" ); document.write( " 3) A is diagonalizable (in C)iff the min. ploy. for A is \n" ); document.write( " the product of distinct linear factors.\r \n" ); document.write( "\n" ); document.write( " Now, clearly,this given matrix has 1 as the unique eigenvalue. \n" ); document.write( " (actually, such matrix ialled unipotent, i.e. (A-I)^k = 0 for some I) \n" ); document.write( " \n" ); document.write( " to find A^2006 , we have to get its min. poly. first. \n" ); document.write( " \n" ); document.write( " Since A - I = \n" ); document.write( " [0, 0, 0, 0 \n" ); document.write( " 0, 0, 0, 0 \n" ); document.write( " 0, 1, 0, 0 \n" ); document.write( " 0, -1, 0, 0] \n" ); document.write( " by dirct computation (A-I)^2 = 0\r \n" ); document.write( "\n" ); document.write( " So, m_A(x) = (x-1)^2 (min. poly.) \n" ); document.write( " Then try to find the remainder of x^2006 divided by (x-1)^2: \n" ); document.write( " Since x^2006 -1 = (x^2 -1) q(x) \n" ); document.write( " [ or sove x^= (x^2-1) q(x) + ax + b for a & b. Don't use brutal force \n" ); document.write( " of long division] \n" ); document.write( " So, x^2006 = 1 mod (x^2 -1) \n" ); document.write( " Therefore A^2006 = I.\r \n" ); document.write( "\n" ); document.write( " Make sure you understand about each step. \n" ); document.write( " By the way, [since nullitt(A-I) = 3 & m(x)=(x-1)^2] \n" ); document.write( " the Jordan Canonical Form for A is (i.e A is similar to) \n" ); document.write( " (1 0 0 0) \n" ); document.write( " (1 1 0 0) \n" ); document.write( " (0 0 1 0) \n" ); document.write( " (0 0 0 1)\r \n" ); document.write( "\n" ); document.write( " Kenny\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |