showing logical argument is valid or invalid
$p\to q$
$q\to (r \lor \lnot p)$
$\lnot r$
therefore, $\lnot p$$p\to (r \lor q)$
$q\to\lnot r$
$r$
therefore, $p$
I believe (1) is valid and (2) invalid. Am I correct?
showing logical argument is valid or invalid
$p\to q$
$q\to (r \lor \lnot p)$
$\lnot r$
therefore, $\lnot p$
$p\to (r \lor q)$
$q\to\lnot r$
$r$
therefore, $p$
I believe (1) is valid and (2) invalid. Am I correct?