Hint Use the Spectral Theorem for the corresponding quadratic form and apply the substitution with orthogonal such that (D diagonal) .
Can anyone help me with coming up with a suitable change of variables for this triple integral? (last part of question)
having trouble getting spherical polars to work, if anyone has any other suggestions it would be great!
this is from here, not a take home test
Course Material for Calculus in Three Dimensions and Applications | Mathematical Institute - University of Oxford