After some clarification on truth tables

[burner1]

As part of my uni course, I've got to the point of covering truth tables and slowly going in to Javascripting. I can get hold of the JS pretty quick actually so that's not too bad as of yet (I know it'll get harder lol) but tbh, I'm struggling a bit with truth table outputs... can any of you lads clarify I've grasped this one correctly:

The difference between:
NOT (A and B) and NOT A and B

Is that the first ones output would deem true if 'either' A or B were false (going by the parenthesis first rule), and the second one's output would be only true if 'Both' were false?

Having trouble even typing an explanation lol.

tia.

[coin-op]

NOT A AND B will be true if A is false and B is true

ie (NOT A) AND B

[nitelife]

coin-op is correct. Its about understanding operator precedence. AND has a lower precedence than NOT which means:

NOT A AND B

Is the same as

(NOT A) AND B

NOT (A AND B) is obviously different (im assuming you understand that the brackets mean do this part first).

[OrangeJuicey]

TO B OR NOT TO B

lol couldn't help myself.

[burner1]

Thanks for the input guys (and the bad joke lol)

So I'm taking this to equate to this screen shot of tables I've put in my document?:



Appreciate your help... long time since I done anything more complex than browsing pron sites

[nitelife]

Your second table is incorrect. The A AND B column is correct, but the 4th column NOT (A AND B) is incorrect.

Since you have a column A AND B, NOT (A AND B) is the inverse of that column (you are NOTing it).

A               B               A AND B               NOT (A AND B)
1               1                    1                          0
1               0                    0                          1
0               1                    0                          1
0               0                    0                          1

Where 0 is false, and 1 is true.

[blacksheep]

!(A&&B)=!A||!B
!A&&!B=!(A||B)