I need help to verify my solutions.
I have two relations.
$(x,y)Pz :\iff x + y = z$ and $(x,y)Mz: \iff x - y = z$
the quest is what is
the symbols are defined like this.
$xP;Qz := \exists y:xpPy \land yQz$
$\text{converse}(xRy) := \{(y,x)|(x,y \in R)\} $
a) $(1,2).P;\text{converse}(M)$
b) $P;\text{converse}(P).(u,v)$
c) $(x,y)(P \cap M).\text{converse}(P\cup M)$
so my solution is:
a) $(1,2)P(3) \text{converse} (M)(x,y||x > y \land x-y=3)$
b) $(u,v)P;\text{converse}(P)(u,v)$
c) I really have problems with c.what I have is
$(x,y)(P∩M)( \emptyset ) .\text{converse}(P∪M) $
I don't know what the last step for c is and I hope someone can tell me if a and b is right.