Eigenvalues and Eigenvectors Calculator

Find the eigenvalues and eigenvectors of $$$\left[\begin{array}{cc}1 & 2\\0 & 3\end{array}\right]$$$.

Start from forming a new matrix by subtracting $$$\lambda$$$ from the diagonal entries of the given matrix: $$$\left[\begin{array}{cc}1 - \lambda & 2\\0 & 3 - \lambda\end{array}\right]$$$.

The determinant of the obtained matrix is $$$\lambda^{2} - 4 \lambda + 3$$$ (for steps, see determinant calculator).

Solve the equation $$$\lambda^{2} - 4 \lambda + 3 = 0$$$.

The roots are $$$\lambda_{1} = 3$$$, $$$\lambda_{2} = 1$$$ (for steps, see equation solver).

These are the eigenvalues.

Next, find the eigenvectors.

1. $$$\lambda = 3$$$

   $$$\left[\begin{array}{cc}1 - \lambda & 2\\0 & 3 - \lambda\end{array}\right] = \left[\begin{array}{cc}-2 & 2\\0 & 0\end{array}\right]$$$

   The null space of this matrix is $$$\left\{\left[\begin{array}{c}1\\1\end{array}\right]\right\}$$$ (for steps, see null space calculator).

   This is the eigenvector.

2. $$$\lambda = 1$$$

   $$$\left[\begin{array}{cc}1 - \lambda & 2\\0 & 3 - \lambda\end{array}\right] = \left[\begin{array}{cc}0 & 2\\0 & 2\end{array}\right]$$$

   The null space of this matrix is $$$\left\{\left[\begin{array}{c}1\\0\end{array}\right]\right\}$$$ (for steps, see null space calculator).

   This is the eigenvector.

Eigenvalue: $$$3$$$A, multiplicity: $$$1$$$A, eigenvector: $$$\left[\begin{array}{c}1\\1\end{array}\right]$$$A

Eigenvalue: $$$1$$$A, multiplicity: $$$1$$$A, eigenvector: $$$\left[\begin{array}{c}1\\0\end{array}\right]$$$A