Let , ..., be Real Integrable Functions over the Closed Interval , then the Determinant of their integrals satisfies
See also Gram-Schmidt Orthonormalization
References
Gradshteyn, I. S. and Ryzhik, I. M. Tables of Integrals, Series, and Products, 5th ed. San Diego, CA:
Academic Press, p. 1100, 1979.