Over the last decade there has been a considerable amount of research
on numerical and analytic aspects of linear and nonlinear differential
algebraic equations (DAEs) F(x', x, t, u) = 0. Many of these papers h
ave either considered linear equations or based their analysis on line
ar equations. However, until very recently there has been little rigor
ous investigation of the relationship between the linearization of a D
AE and the original equations. In this paper we carefully examine seve
ral aspects of this relationship. Positive results for time varying li
nearization and counter examples for time invariant linearization are
given.