Suppose \(A\) is an \(n\times n\) complex matrix with \(n>1\). If \(A\) has rank 1, prove that \(A\) is similar to a diagonal matrix if, and only if, \(\operatorname {trace}(A)\ne 0\). [The trace of a matrix is the sum of the entries on the main diagonal.]
Question
Math 6310 • Algebra
Fall 2003 • Question 2