The dual of the statement ∼p∧[∼q∧(p∨q)∧∼r] is:
The dual of statement p∨(q∧r)≡(p∨q)∧(p∨r) is
Factorise: (p2+q2−r2)2−4p2q2
The contrapositive of (∼p∧q)→(q ∧∼r) is