HOMEWORK 7-2.


1. Sketch the steps of the unification algorithm on the pairs below:

a) f(a,x,g(y)) and f(z,y,x)
b) f(x,y,z,w) and f(f(u,u),f(x,x),f(y,y),f(z,z))

f and g are function symbols, x,y,z,u,w are variables, a,b,c,d are constants.