SOLUTION: Is this argument valid or invalid? Can you help me construct a truth table? Thank you for your help! T v P, P ├ -T

Algebra ->  Proofs -> SOLUTION: Is this argument valid or invalid? Can you help me construct a truth table? Thank you for your help! T v P, P ├ -T      Log On


   

Question 980260: Is this argument valid or invalid? Can you help me construct a truth table? Thank you for your help!
T v P, P ├ -T
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
If "T" is a truth value constant (representing True), then ~T is false

The conclusion is always false. The premise T v P is always true because of the "T". The premise P has the possibility of being true if P = T. So as long as P = T, then all premises are true with a false conclusion. So this leads to an invalid argument.

Truth table:

T v PP~T
TTF
TFF