Proving Matrix Equality: A^3+4A^2-2A+7i=0 Implies A^T Also Satisfies It?

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ahmed dawod
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1. show that if a square matrix A satisfies A^3+4A^2 -2A+7i=0 then so does A^T

i is the identity matrix






The Attempt at a Solution



I tried to multiply the equation by A^T but all in vain
 
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Use:
(A+B)^T = A^T + B^T \qquad (AB)^T = A^TB^T \qquad (cA)^T = cA^T
to compute the transpose by using:
0 = 0^T = (A^3 + 4A^2 - 2A + 7I)^T
 
thanks
this is useful

problem solved:biggrin:
 
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