YES Time: 0.282 Problem: Equations: plusAC(plusAC(x2,x3),x4) -> plusAC(x2,plusAC(x3,x4)) plusAC(x2,x3) -> plusAC(x3,x2) plusAC(x2,plusAC(x3,x4)) -> plusAC(plusAC(x2,x3),x4) plusAC(x3,x2) -> plusAC(x2,x3) TRS: f(plusAC(x,y)) -> plusAC(f(x),f(y)) plusAC(x,0()) -> 0() f(0()) -> 0() Proof: Matrix Interpretation Processor: dimension: 2 interpretation: [0] [0] = [6], [2 4] [2] [f](x0) = [0 4]x0 + [4], [4] [plusAC](x0, x1) = x0 + x1 + [2] orientation: [2 4] [2 4] [18] [2 4] [2 4] [8 ] f(plusAC(x,y)) = [0 4]x + [0 4]y + [12] >= [0 4]x + [0 4]y + [10] = plusAC(f(x),f(y)) [4] [0] plusAC(x,0()) = x + [8] >= [6] = 0() [26] [0] f(0()) = [28] >= [6] = 0() problem: Equations: plusAC(plusAC(x2,x3),x4) -> plusAC(x2,plusAC(x3,x4)) plusAC(x2,x3) -> plusAC(x3,x2) plusAC(x2,plusAC(x3,x4)) -> plusAC(plusAC(x2,x3),x4) plusAC(x3,x2) -> plusAC(x2,x3) TRS: Qed