First Order Logic, help in Unification and substitution process

Question

I'm trying to solve a few unification problems, but this one is a bit tricky to me. I have to demonstrate how to derive the first one starting from the second one.

$\phi$ (c, f(c,h(M,e(c)))

$\phi$ (X, f(X,h(c,V))

considering that upper case letter are variables, else constants and function symbols.

This a cascade unification problem but how to solve this?

Answer 1

When unifying you don't 'derive' the one from the other ... rather, you make substitutions for each of the terms so they match up.

So, use:

$X \leftarrow c$, $M \leftarrow c$, and $V \leftarrow e(c)$