take 1
P V (Q -> R)=true
But (Q -> R) = ¬Q V R
so 1 is
P V ¬Q V R
Law of negation
¬¬(P V ¬Q V R)
¬(¬P ^ ¬¬Q ^ ¬R)
¬(¬P ^ Q ^ ¬R)
from 2 Q^~R =true
¬(¬P ^ Q ^ ¬R)
¬(¬P ^ true)
identity law (P ^true)=P
¬(¬P)
P
take 1
P V (Q -> R)=true
But (Q -> R) = ¬Q V R
so 1 is
P V ¬Q V R
Law of negation
¬¬(P V ¬Q V R)
¬(¬P ^ ¬¬Q ^ ¬R)
¬(¬P ^ Q ^ ¬R)
from 2 Q^~R =true
¬(¬P ^ Q ^ ¬R)
¬(¬P ^ true)
identity law (P ^true)=P
¬(¬P)
P