1.Show that $\neg((\neg p\land q)\lor(\neg p\land \neg q))\lor(p\land q)\equiv p.$
$\neg((\neg p\land q)\lor(\neg p\land \neg q))\lor(p\land q)\equiv \neg(\neg p\land ( q\lor \neg q))\lor (p\land q)\equiv \neg(\neg p\land q)\lor (p\land q)\equiv (p\lor \neg q)\lor (p\land q).$
I stuck here. I am very beginner in logics and propositional calculus. Any help will be appreciated.