document.write( "Question 1159576: Solve for X. Assume X is a 2×2 matrix. Do not use decimal numbers in your answer. If there are fractions, leave them unevaluated.
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Algebra.Com's Answer #782634 by ikleyn(52944)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "You are given a matrix equation\r\n" );
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document.write( "    B - X*A = I.\r\n" );
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document.write( "where B, A and I are given  2x2-matrices.\r\n" );
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document.write( "Re-write it in the form\r\n" );
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document.write( "    X*A = C,       (1)\r\n" );
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document.write( "where  C = B - I.\r\n" );
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document.write( "Now, the matrix A is non-degenerated (since its determinant is not zero).\r\n" );
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document.write( "Therefore, the inverse matrix  \"A%5E%28-1%29\"  does exist.\r\n" );
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document.write( "Calculate the inverse matrix  \"A%5E%28-1%29\",  using your knowledge of linear/(matrix) algebra.\r\n" );
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document.write( "Then multiply equation (1)  by the matrix  \"A%5E%28-1%29\"  from the right side.\r\n" );
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document.write( "You will get then the solution \r\n" );
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document.write( "    X = \"C%2AA%5E%28-1%29\".\r\n" );
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\n" ); document.write( "\n" ); document.write( "If it is allowed to you to use a calculator for matrix calculations, you can use it . . . \r
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