document.write( "Question 1062853: an n x n matrix A is nilpotent if A^r=0 for some positive integer
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\n" ); document.write( "(b)show that if A is invertible matrix,then A is not nilpotent
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Algebra.Com's Answer #677872 by ikleyn(52797)\"\" \"About 
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\n" ); document.write( "an n x n matrix A is nilpotent if A^r=0 for some positive integer
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\n" ); document.write( "(b)show that if A is invertible matrix,then A is not nilpotent
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document.write( "a) An example is A = \"%28matrix%282%2C2%2C+0%2C1%2C+0%2C0%29%29\". Check that \"A%5E2\" = 0.\r\n" );
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document.write( "b) If a matrix A is nilpotent, then det(A) = 0  (determinant).\r\n" );
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document.write( "   From the other side, if a matrix A is invertible, then its determinant is not zero.\r\n" );
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