Q47.Marks: +2.0UGC NET Paper 2: Computer Science 26th Nov 2021
Consider the sentence below.
There is a country that borders both India and Pakistan.
Which of the following logical expressions express the above sentence correctly when the predicate Country(x) represents that x is a country and Borders(x, y) represents that the countries x and y share the border?
Border(c, India) = For every c, select those c which shares border with India
Border(c, Pakistan) = For every c, select those c which shares border with Pakistan
∧ - Do and operation for all the above three statements - All the 'c' will be selected which is a country and it shares a border with India and Pakistan each.
Border(c, India) = For every c, select those c which shares border with India
Border(c, Pakistan) = For every c, select those c which shares border with Pakistan
Make a list of all the common 'c' found after AND operation between the above two.
Country(c) = All the countries
Make a list of all the countries 'c'.
NOTE: '⇒' symbol is defined as 'implies'. That means, every country will share the border with India and Pakistan which is not necessarily true.
∃c Border (Country(c), India ∧ Pakistan): INCORRECT
Explanation:
Border (Country(c), India ∧ Pakistan) is not correct statement.
Border(x, y) means x and y share a border, where x and y are countries but here, India ∧ Pakistan is given in place of 'y' which is semantically wrong.