We consider the following Problem: Strict Trs: { and(x, or(y, z)) -> or(and(x, y), and(x, z)) , and(x, and(y, y)) -> and(x, y) , or(or(x, y), and(y, z)) -> or(x, y) , or(x, and(x, y)) -> x , or(true(), y) -> true() , or(x, false()) -> x , or(x, x) -> x , or(x, or(y, y)) -> or(x, y) , and(x, true()) -> x , and(false(), y) -> false() , and(x, x) -> x} StartTerms: basic terms Strategy: innermost Certificate: YES(?,O(n^2)) Proof: Arguments of following rules are not normal-forms: { and(x, and(y, y)) -> and(x, y) , or(x, or(y, y)) -> or(x, y)} All above mentioned rules can be savely removed. We consider the following Problem: Strict Trs: { and(x, or(y, z)) -> or(and(x, y), and(x, z)) , or(or(x, y), and(y, z)) -> or(x, y) , or(x, and(x, y)) -> x , or(true(), y) -> true() , or(x, false()) -> x , or(x, x) -> x , and(x, true()) -> x , and(false(), y) -> false() , and(x, x) -> x} StartTerms: basic terms Strategy: innermost Certificate: YES(?,O(n^2)) Proof: We consider the following Problem: Strict Trs: { and(x, or(y, z)) -> or(and(x, y), and(x, z)) , or(or(x, y), and(y, z)) -> or(x, y) , or(x, and(x, y)) -> x , or(true(), y) -> true() , or(x, false()) -> x , or(x, x) -> x , and(x, true()) -> x , and(false(), y) -> false() , and(x, x) -> x} StartTerms: basic terms Strategy: innermost Certificate: YES(?,O(n^2)) Proof: The following argument positions are usable: Uargs(and) = {}, Uargs(or) = {1, 2} We have the following restricted polynomial interpretation: Interpretation Functions: [and](x1, x2) = 3 + 2*x1 + 3*x1*x2 + 3*x2^2 [or](x1, x2) = 2 + x1 + 3*x2 [true]() = 0 [false]() = 0 Hurray, we answered YES(?,O(n^2))