Learn and revise how to solve quadratic equations by factorising, completing the square and using the quadratic formula with GCSE Bitesize AQA Maths.

In the general case the quadratic forms Qk determine many-electron functions formed from correlated electron orbitals of ellipsoidal symmetry and with variable centres. The results are easily extended ...

The estimation of quadratic functions of a multivariate normal mean is an inferential problem which, while being simple to state and often encountered in practice, leads to surprising complications ...