Matrix A is diagonalizable when A is similar to a
diagonal matrix
A is diagonalizable when there
exists an invertible matrix P such
that is a diagonal matrix
Matrix B is said similar to matrix A if
there is a nonsingular matrix P such that
If A and B are similar n x n
matrices, then they have
the same eigenvalues
Condition for diagonalization : A is
diagonalizable iff it has n linearly
independence eigenvectors
If the eigenvalues of an n x n matrix A are
all distinct, then A is diagonalizable
Prodcedure for Diagonalizing An n x n
Matrix A
Step 1: Find eigenvalue
Step 2: Form matrix P
Step 3: The matrix D = P^(-1)AP will be a diagonal with its
principal diagonal entries are the eigenvalues corresponding
to eigenvectors.
Symmetrix Matrices & Orthogonal Matrix
A square matrix A is
symmetric when it is equal to
its transpose
Properties of Symmetric Matrices
1. A is diagonalizable
2. All eigenvalue of A are real
3. If lambda is an eigenvalue of A with multiplicity k,
then lambda has k linearly independent eigenvectors.
That is eigenspace of lambda has dimension k.
A nonsingular matrix A is called orthogonal
matrix if A inverse = A transpose
The n x n matrix A is orthogonal iff the column (rows) of A
form an orthonormal set of verctors in R^n
Let A be an n x n symmetric matrix . If
lambda 1 and lambda 2 are distinct
eigenvalues of A, then corresponding
eigenvectors x1 and x2 are orthogonal
If A is a symmetric n x n matrix, then there exists an
orthogonal matrix P such that (below) is a diagonal matrix
Eigenvector Problem
Diagonalization Problem: whether there
exist or not an invertible matrix P such
that (below) is a diagonal matrix?
If A is an n x n matrix, then A is diagonalizable and
A has n linearly independent eigenvectors
Distinct eigenvalues of A -> Distinct eigenvectors of A -> then eigenvectors is a Linearly Independent set
If A is n x n diagonalizable square matrix
and (below) is the diagonal matrix, then