| In this paper we discuss a problem about Gronwall inequality for projected systems, which was mentioned in Hale′s book. An estimate for nonnegative bounded continuous function ｕ（ｔ）≤ａ（ｔ）＋∫０tｂ（ｔ－ｓ）ｕ（ｓ）ｄｓ＋∫０∞ｃ（ｓ）ｕ（ｔ＋ｓ）ｄｓ，(?)ｔ≥０ is given. The conclusion is useful for investigating bounded solutions, invariant manifolds and its foliations for differential equations, and for further discussion on Gronwall inequality with singularity. |
