Show that ifa is a subset of a universal setu, thena) A ? A = ?.________________b) A ? ? = A.________________c) ________________d)

Solution:Step1We have to show that if a is a subset of a universal set u. Step2a) A A = .L.H.S(left hand side)=R.H.S(right hand side)=Let x be an arbitrary element .L.H.S= = = = = ( As = = = R.H.SSo, A A = Step3b) A = A.L.H.S(left hand side)=R.H.S(right hand side)=ALet x be an arbitrary element .L.H.S=A = = = = ( where u is an universal set)...