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Linear AlgebraChallengeDiagonalization & Matrix Powers

Diagonalization & Matrix Powers · Challenge problem

Power iteration repeatedly multiplies a vector by a matrix AA and renormalizes; the error in the estimated dominant eigenvector shrinks by a factor of roughly ∣λ2λ1∣\left|\dfrac{\lambda_2}{\lambda_1}\right| every step, where λ1,λ2\lambda_1,\lambda_2 are the two eigenvalues of AA with the largest absolute values. For a matrix with eigenvalues 66 and 22, find the smallest number of iterations nn for which (26)n<0.01\left(\dfrac{2}{6}\right)^n < 0.01.