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Find the eigenvalues and associated unit eigenvectors of the (symmetric) matrix

A = [ 1 5 ]
[ -8 -11 ]

smaller eigenvalue =
associated unit eigenvector =
larger eigenvalue =
associated unit eigenvector =

User Impl
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Final answer:

To find the eigenvalues of the given matrix, we solve the characteristic equation det(A - λI) = 0 by expanding the determinant and simplifying. The resulting eigenvalues are λ₁ = -3 and λ₂ = -9. To find the unit eigenvectors corresponding to each eigenvalue, we solve the equation (A - λI)x = 0 and find the solutions for x.

Step-by-step explanation:

We start by finding the eigenvalues λ. To do this, we solve the characteristic equation det(A - λI) = 0, where A is the given matrix and I is the identity matrix.

For the matrix A = [[1, 5], [-8, -11]], the characteristic equation is:

det([[1, 5], [-8, -11]] - λ[[1, 0], [0, 1]]) = 0

By expanding the determinant and simplifying the equation, we get:

λ² + 10λ + 27 = 0

Solving this quadratic equation, we get the eigenvalues λ₁ = -3 and λ₂ = -9.

To find the unit eigenvectors corresponding to each eigenvalue, we solve the equation (A - λI)x = 0, where x is a column vector.

For eigenvalue λ₁ = -3:

Solving (A - (-3)I)x = 0, we get:

[4, 5]x = 0

The solution to this system of linear equations is x = [-5, 4].

For eigenvalue λ₂ = -9:

Solving (A - (-9)I)x = 0, we get:

[10, 5]x = 0

The solution to this system of linear equations is x = [-1, 2].

Therefore, the eigenvalues of matrix A are λ₁ = -3 and λ₂ = -9, and the corresponding unit eigenvectors are [-5, 4] and [-1, 2].

User Tarlen
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