Question

Help!! Please.
Use truth tables to test the validity of the argument.

p → ~q
q → ~p
∴ p ∨ q

Answer 1

I have to think about this one.

Answer 2

here it says that P is approach to equivalent Q
and Q is approach to equivalent P
so it means both are equal
therefore it show in the end
P union Q

Answer 3

Ok. I really don't know how to do this either.

Answer 4

@phi am i correct?

Answer 5

I'm supposed to write a table for this.

Answer 6

@ganeshie8 Can you help me?

Answer 7

I would start by writing out the truth table for
p-> ~q ( equivalent to ~p v ~q)
and
q → ~p ( same as ~q v ~p )

Answer 8

so p=q

Answer 9

I'm like sooo confused. Right now. I have no clue why.

Answer 10

I think the idea is to show when the premises
p → ~q
q → ~p
are true, then so is the conclusion p v q

the truth table for p-> ~q is the truth table of ~p v ~q and it is identical to the truth table for q -> ~p (= ~q v ~p)

so we we want to show that the truth table of

~p v ~q matches p v q

however, ~p v ~q = ~(p ^ q) and this is clearly not the same as q v q

the table will show that when ~p v ~q is T, there will be an instance where p v q is F

in other words, this argument is invalid

Answer 11

Ok. I think I understand it now. Thanx soooo much though:)