Approximations of -Fuzzy Hyperideals in Ordered LA-Semihypergroups

摘要

This paper concerns the relationship between rough sets, - fuzzy sets, and the LA-semihypergroups. We proved that the lower approximation ( - approx) and the upper approximation ( - approx) of different hyperideals of LA-semihypergroups become again hyperideal and also provided some examples. We also provided a result which shows that, if is not a hyperideal of an LA-semihypergroup , then its lower approximation is also not a hyperideal.