and Applied Analysis 3 In this paper, L always denotes a complete residuated lattice unless otherwise stated, and L denotes the set of all L-subsets of a nonempty set X. For all A,B ∈ L , we define A ∩ B x A x ∧ B x , A ∪ B x A x ∨ B x , A ∗ B x A x ∗ B x , A −→ B x A x −→ B x . 2.1 Then L, ∗, → ,∨,∧, 0, 1 is also a complete residuated lattice. If no confusion arises, we always do not discrimin...