The Determinant
摘要
Every square matrix A has a determinant \(\det (A)\) . With this characteristic of A, we can provide a crucial invertibility criterion for A: A square matrix A is invertible if and only if \(\det (A) \neq 0\) . This criterion is what makes the determinant so useful: We can use it to calculate the eigenvalues and thus solve the crucial problems in engineering sciences, such as principal axis transformation or singular value decomposition.