New posts in Quadratic Forms

Why do positive definite matrices have to be symmetric?

Solving a quadratic 9-equation system

Is the quadric $3$-fold $v^2 + w^2 + x^2 + y^2 + z^2 = 0$ isomorphic to $P^3$?

Dimension of totally isotropic subspaces for a given quadratic form

reference for linear algebra books that teach reverse Hermite method for symmetric matrices

$x^2+y^2+z^2=5(xy+yz+zx)$ -- Is this all solutions?

Why is quadratic form defined via a symmetric bilinear form?

Minimum of a quadratic form

Is it true that the whole space is the direct sum of a subspace and its orthogonal space?

How to calculate the gradient of $x^T A x$?