Past exam of the mathematics course of the University of Cambridge 2005 iii Paper 79 4 a iii Solution Created 2026-10-03 Updated 2026-10-14
For and positive amplitude , the averaged amplitude for position-dependent damping givesThe average is . Thus the absolute-value damping amplitude law isand as in the other cases. Consequently,The dissipation makes the leading envelope decrease algebraically in slow time. The absolute value is Lipschitz continuous, so the first-order averaging argument remains valid despite its corner at zero.