Mathematical Logic

@arjunsuresh:disqus I want to discuss how to decide validity of complicated First order Predicate expression.

Following Questions I want to be discussed (Note that I’ve already been able to solve most of these, but I want them to be discussed for more clarity & if something this difficult gets asked ! ) ->
http://gateoverflow.in/10436/propositional-logic
http://gateoverflow.in/20939/tifr2012-a-2
http://gateoverflow.in/20981/tifr2012-a-3
http://gateoverflow.in/923/gate2003_33
http://gateoverflow.in/26748/gate1991-15-b

Other good candidate for discussion ->
http://gateoverflow.in/25994/tifr2014-a-8
http://gateoverflow.in/922/gate2003_32