We say $\lambda$ is an eigenvalue of a square matrix $A$ if $Ax = \lambda x$.
Now, i want two examples of a matrix like $A$.
The first one, $A$ should have just one eigenvalue which should be $0$.
The second one, $A$ should be a matrix in which $a_1,\dots,a_n$ are eigenvalues. ( They give $a_i$'s and want the matrix )
Note : I have no idea how to find these matrices. I don't know where to start ...