Hill's Differential Equation
The second-order ordinary differential equation
![(d^2y)/(dx^2)+[theta_0+2sum_(n=1)^inftytheta_ncos(2nx)]y=0,](http://mathworld.wolfram.com/images/equations/HillsDifferentialEquation/NumberedEquation1.gif) |
(1)
|
where
are fixed constants. A general solution can be given by taking the "determinant" of an infinite matrix.
If only the
term is present, the equation have solution
 |
(2)
|
If terms
are included, the equation becomes the Mathieu differential equation, which has solution
 |
(3)
|
If terms
are included, it becomes the Whittaker-Hill differential equation.
REFERENCES:
Hill, G. W. "On the Part of the Motion of Lunar Perigee Which is a Function of the Mean Motions of the Sun and Moon." Acta Math. 8, 1-36, 1886.
Ince, E. L. Ordinary Differential Equations. New York: Dover, p. 384, 1956.
Magnus, W. and Winkler, S. Hill's Equation. New York: Dover, 1979.
Zwillinger, D. Handbook of Differential Equations, 3rd ed. Boston, MA: Academic Press, p. 123, 1997.