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Let s represent a false statement and let r represent a false statement. Find the truth value of the following statement.

~[~s v (~ r < s ) ]
Is the statement true or false?
True
False

1 Answer

4 votes

I'll interpret the given statement as


\\eg \bigg( \\eg s \lor \big( \\eg r \land s \big) \bigg)

where
\\eg x means "not x",
\lor means "or", and
\land means "and".

If r is false, then
\\eg r is true.

s is given to be false, so
\\eg r\land s (basically "true and false") is false.

If s is false, then
\\eg s is true.

Then
\\eg s \lor \big(\\eg r \land s\big) (i.e. "true or false") is true.

Take the negation of that and you end up with a false statement.

If you intended "~r < s" to mean something like "not r is implied by s", so the original statement is actually


\\eg\bigg(\\eg s \lor \big(\\eg r \impliedby s \big)\bigg)

then
s\implies \\eg r is true because s is false. Then
\\eg s \lor \big(\\eg r \impliedby s\big) is still true, so the statement still ends up being false.

User Axemasta
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