Let W (x, y) mean that student x has visited website y, where the domain for x consists of all students in your school and the domain for y consists of all websites. Express each of these statements by a simple English sentence.

a) W (Sarah Smith, www.att.com)
b) ∃xW(x, www.imdb.org)
c) ∃yW(José Orez, y)
d) ∃y(W(Ashok Puri, y) ∧ W(Cindy Yoon, y))
e) ∃y∀z(y ≠ (David Belcher) ∧ (W(David Belcher, z) → W(y,z)))
f) ∃x∃y∀z((x ≠ y) ∧ (W (x, z) ↔ W (y, z))).

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obiefule111 obiefule111 · Answer 1 · 2020-02-04T21:54:57+01:00

Answer:

a) sarah smith has visited www.att.com

b) imdb.org has been visited by x

c)jose orez has visited some website

d)ashok, puri, cindy, yoon have visited website y

e)if a website z is there, z must have visited the website if David has also visited

f)2 persons are there. for each website, either of them will visit the site only when the other visits website z

Step-by-step explanation:

a)W(x,y)= student x visited website y

domain x= students in your school

domain y= websites

b) x is existing and x has visited the website or it has been visited by someone]

c) it means y is existing which was visited by jose

d)y is existing and the 4 students visited website y

e) there is neither a person y nor David Belcher who visited all websites David belcher visited

f) 2 persons are there and they're not equal to each other. 2 persons are there who have visited the same websites