| A | É | (B | · | C) | / | (B | v | D) | É | C | // | A | É | (B | v | D) | |
|
T | T | T |
F | F |
F | F | ||||||||||
B and D must both be false for the v to be false. So fill in those truth values. Now I have all the truth values for all the statements in the conclusion. The next step it to start transferring them to the premises. Click here to see that.