Homework on §2.2--assigned Wed 9/6 and due Fri 9/8
Construct a derivation to show: A ∧ B, (C ∧ D) ∧ E ⇒ C ∧ (B ∧ D).
(Notice that this is the same as showing that the argument
is valid. That means that your derivation should begin with the resources A ∧ B and (C ∧ D) ∧ E on separate lines.)