Document Type: Research Paper


1 College for professional studies for teachers, Sabac, Serbia

2 College for professional studies for teachers,Sabac, Mega- trend University, Beograd, Serbia

3 Department of Mathematics and Informatics, University of Novi Sad, Novi Sad, Serbia


In the framework of fuzzy algebras with fuzzy equalities and a
complete lattice as a structure of membership values, we investigate fuzzy
equational classes. They consist of special fuzzy algebras ful lling the same
fuzzy identities, de ned with respect to fuzzy equalities. We introduce basic
notions and the corresponding operators of universal algebra: construction of
fuzzy subalgebras, homomorphisms and direct products. We prove that every
fuzzy equational class is closed under these three operators, which means that
such a class is a fuzzy variety.


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