Re: Need to check this work

can anybody help ?

thanks

Re: Need to check this work

I think this is correct. (In (b), you need to insert a space between \Rightarrow and M.)

I am not sure if your problem allowed defining individual constants along with predicates. In (e) you did define j and r. For example, (c) could be ∀x (L(x,m) <-> x ≠ m) where L(x,y) means x likes y and m means Mary.

It is easier to read formulas if predicates are named mnemonically, e.g., C(x) for calculus, S(x,y) for saw, etc.

Re: Need to check this work

thanks makarov

so b) will be

$\displaystyle \forall x \left[R(x)\Rightarrow \neg\left(\forall y\left[Q(y)\Rightarrow M(x,y)\right]\right)\right]$

c) becomes much simpler with your approach, thanks