Thread: NOT and AND

how do you show that A⇒B is equivalent to (NOT A) OR B?

i tried but i cant get the answer

A B NOT A A⇒B (NOT A) OR B
T F F T F
T F F F T
F T T T T
F F T T F

this is in the format of a table where the first row is the heading and the subsequent rows are cases when A and B and TRUE and FALSE.


i tried to prove ti as seen above but im not able to show that they are equivalent. someone please help..


Thanks!

Originally Posted by alexandrabel90

how do you show that A⇒B is equivalent to (NOT A) OR B?

i tried but i cant get the answer

A B NOT A A⇒B (NOT A) OR B
T F F T F
T F F F T
F T T T T
F F T T F

this is in the format of a table where the first row is the heading and the subsequent rows are cases when A and B and TRUE and FALSE.


i tried to prove ti as seen above but im not able to show that they are equivalent. someone please help..


Thanks!

This table has some problems. Let's start over. Make one table for the statement (not)A or B, and make another one for A implies B.

The second table isn't hard. Do you get what (not)A or B means? Remember that an "or" statement is true if either one of the separate statements are. So the only way A or B is false is when A is false and B is false.

You haven't responded to any of the threads I've answered. You should finish your current problems before posting more because you might make insights so you don't need to ask anything else.

based on
A B A⇒B
T T T
T F F
F T T
F F T


A B (NOT A) OR B
T T T
T F F
F T T
F F T

Oh i got it!

Thank you so much.. I was so confused with (not a) or b!

Thanks!!!(:

by the way, i have already replied you in the other post(:

Here's a very handy online truth table program:

Brian's Project Gallery - Truth Table Constructor

Great time saver!