Volume 1, Issue 1, August 2017, pp 30-41
Department of Mathematics, Periyar University, Salem - 636 011, TN, India.
In this paper we introduce FFI-projective, FFI-injective and FFI-ﬂat modules and give a characterization of FFI-injective modules and FFI-projective modules. When all left R-modules has FI-injective covers, we show that a left R-module is FFI-injective if and only if M is a direct sum of an injective left Rmodule and a reduced FFI-injective left R-module. Class of all FFI-injective left R-modules is closed under direct limits whenever all modules has FFI-injective cover. Furthermore, we show that class of all FFI-projective modules is closed under inverse limits whenever every left R-module has an epic FFI-projective envelope.
FFI-injective module, FFI-ﬂat module, FFI-projective module,(Pre)envelope, (Pre)cover.
Subject classification: 16D10, 16D40, 16E30.
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