[Mathematical logic] prenex normal form and skolem normal form

1 reply · 2K views · last reply
Nico
Messages
2
Reaction score
0
Homework Statement
[Mathematical logic] convert the following equation into prenex normal form and skolem normal form.
Relevant Equations
(a) ~∃x∃y(~p(x) ∧ ∀z q(y, z) )


(b) ∀x ( p(x) ⇔ ∃y q(y, x) )


(c) ~(∀p(x)∧∀y∃zq(y, z)∧∀y∃z q(z, y))
The attached picture below is the note I solved halfway through.

Please tell me the entire process of getting to the correct answer.
 
Attachments
  • Handwritten derivation converting first-order logic formulas to prenex normal form and then Skolem normal form, with each step written on a separate line with an equals sign and labelled with a note.
    18(a)(b).png
    13.2 KB · Views: 204
  • Handwritten derivation of a prenex normal form transformation, steps labelled (c), with a question mark where the working stops; expressions use quantifiers over x, y, z and predicates P, Q and phi.
    18(c).png
    6.2 KB · Views: 188
@Nico, we discourage the use of images that show work done, because they are usually illegible due to small image size or otherwise difficult to read.
Please show your work either as text or preferably, using LaTeX. There is a link to our tutorial at the lower left corner of the text entry pane.