YES (VAR x1 x0 x y z) (RULES inverse(multiply(x1,x0)) -> multiply(inverse(x0),inverse(x1)) multiply(x1,multiply(inverse(x1),x0)) -> x0 inverse(identity()) -> identity() inverse(inverse(x0)) -> x0 b() -> inverse(c()) multiply(x0,identity()) -> x0 multiply(x0,inverse(x0)) -> identity() multiply(inverse(x1),multiply(x1,x0)) -> x0 multiply(inverse(x),x) -> identity() multiply(identity(),x) -> x multiply(multiply(x,y),z) -> multiply(x,multiply(y,z)) ) (COMMENT Termination is shown by KBO with weight w0 = 2 w(multiply) = 0 w(identity) = 3 w(inverse) = 0 w(c) = 3 w(b) = 4 and precedence: inverse > multiply > identity > c > b )