[Mathematical logic] prenex normal form and skolem normal form

Nico
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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.
 

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@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.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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