woodpecker 0 #1 December 10, 2007 Does anyone understand them? Having a hard time grasping how the output portion actual adds up. Here is an example: A B A.B A+A.B 0 0 0 0 0 1 0 0 1 0 0 1 1 1 1 1 above is the truth table. How does A.B = 0 0 1 1 and hw the hell does A+A.B = 0 0 1 1 I'm missing something and it isnt coming to me. thanks in advance, BillySONIC WOODY #146 There is a fine line between cockiness and confidence -- which side of the line are you on? Quote Share this post Link to post Share on other sites
base689 0 #2 December 10, 2007 It is all correct. Provided that boolean '+' yields 1 when at least one between A and B is 1 and that boolean "·" yields 1 only when both A and B are 1, we have the A·B column which is correct. Then we have the "+" operation between "A" and "A·B", in fact we have 1 only when at least one between "A" and "A·B" is 1: A _ B _ A·B _ A+A·B 0 _ 0 __ 0 ___ 0 0 _ 1 __ 0 ___ 0 1 _ 0 __ 0 ___ 1 1 _ 1 __ 1 ___ 1 Please consider that B is NOT any of direct member of boolean sum but comes into play only to determine the result of "A·B": FIRST you do "A·B" and THEN you do "A+(A·B)", where "A·B" is the second member.Stay safe out there Blue Skies and Soft Walls BASE #689 - base_689AT_NO_123_SPAMyahoo.com Quote Share this post Link to post Share on other sites
shropshire 0 #3 December 10, 2007 <> Yes... As Base said:- A AND B is the same as A&B is the same as A.B (so both A and B must = 1 for the output to be 1 otherwise it's 0) A OR B is the same as A+B (so if either A is 1 or B is 1 then the output is 1 otherwise it's 0) (.)Y(.) Chivalry is not dead; it only sleeps for want of work to do. - Jerome K Jerome Quote Share this post Link to post Share on other sites
grannyinthesky 0 #4 December 10, 2007 Quote<> Yes Me too. Logic was one of my favorite classes, both math and philosophy."safety first... and What the hell..... safety second, Too!!! " ~~jmy POPS #10490 Quote Share this post Link to post Share on other sites
cocheese 0 #5 December 10, 2007 I can't handle the truth. Quote Share this post Link to post Share on other sites
jimstermer 0 #6 December 10, 2007 Anyone up for some P or NP complete fun? Quote Share this post Link to post Share on other sites
grannyinthesky 0 #7 December 10, 2007 Whatcha got in mind?"safety first... and What the hell..... safety second, Too!!! " ~~jmy POPS #10490 Quote Share this post Link to post Share on other sites
woodpecker 0 #8 December 10, 2007 Thanks for clearing it up. I finally got it down with the help from this thread and some more painfull reading.SONIC WOODY #146 There is a fine line between cockiness and confidence -- which side of the line are you on? Quote Share this post Link to post Share on other sites
SuperGirl 0 #9 December 10, 2007 Quote Anyone up for some P or NP complete fun? hell yeah! by the way, my prof keeps saying that we KNOW P is not equal to NP... we know it in our gut Quote Share this post Link to post Share on other sites
