document.write( "Question 1109397: proof :
\n" ); document.write( "A^n is invertible and A^n.-1 = A^-n . \n" ); document.write( "

Algebra.Com's Answer #724382 by ikleyn(53763) $\"\"$ $\"About$

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\n" ); document.write( "Since your formulation is far from to be perfect, I will edit the formulation:\r
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\n" ); document.write( "\n" ); document.write( " Prove:\r
\n" ); document.write( "\n" ); document.write( " If A is invertible matrix, then $\"%28A%5En%29%5E%28-1%29\"$ = $\"A%5E%28-n%29\"$ .\r
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document.write( "I will prove it for n = 2, and you will see from there how to do it in the general case.\r\n" );
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document.write( "We are given that   = I.\r\n" );
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document.write( "Then   =  =  =  =  = I.\r\n" );
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document.write( "QED.\r\n" );
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