Computational Physics, Linear Algebra, Math, Mathematics, Science.
can see that a gives you the number of (x_1)², (b+c) the number of (x_1, x_2) and d the number of (x_2)². This means that the same quadratic form can be obtained from infinite number of matrices A by changing b and c while preserving their sum. Note: If A is a diagonal matrix (all 0 except the