Let U be universe under consideration, and let P(x) and Q(x) be predicate with free variable x. Find a useful denial for (∀x∈U)(P(x)⇒Q(x))(adsbygoogle = window.adsbygoogle || []).push({});

Then my answer is:

¬(∀x∈U)(P(x)⇒Q(x))

(∃x∈U)¬(P(x)⇒Q(x))

¬(P(x)⇒Q(x))

¬P∨Q

I'm unsure if I am on the write path when it comes to finding the useful denial, is this how to do it?

Thank you.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# I Finding useful denial

Have something to add?

**Physics Forums | Science Articles, Homework Help, Discussion**