Linear endomorphism/R^2/Upper triangular matrix/Exercise

Determine the eigenvectors and the eigenvalues for a linear mapping

$\varphi \colon \mathbb {R} ^{2}\longrightarrow \mathbb {R} ^{2},$

given by a matrix of the form ${}{\begin{pmatrix}a&b\\0&d\end{pmatrix}}$.

Create a solution