1. What is the coefficient matrix for the quadratic form q(x,y)=x^2+6xy+7y^2?
2. Is the quadratic form q(x,y)=x^2+6xy+7y^2 positive definite?
3. How to judge a matrix is positive definite?
4. If v and w are two vectors in a complex vector space and their inner product
5. The Hermitian dot product of two vectors [1+i, 2]T and [-3i, 4]T is equal to?