A boolean expression (help)

JC-Retro · 20 Mar 2010 at 21:32

I've been looking at this for ages and I think I'm just second guessing myself too much so to put me out of my misery can I (out of sheer kindness

) see some answers to the following question?:

(p AND (q AND NOT(r AND p))) OR NOT(p OR NOT(r))

Basically I have to produce a Venn Diagram, a truth table and find its disjunctive normal form. It looks easy to me but I keep second guessing the final answer for the DNF for whatever reason.

SlyReaper · 20 Mar 2010 at 21:40

I think that simplifies down to p OR q OR r, just from sketching my own Venn diagram.

Actually I think that's wrong. One minute...

gumbald · 20 Mar 2010 at 21:48

Whoa. Long time since I did this. So I'll say:

42

JC-Retro · 20 Mar 2010 at 21:52

SlyReaper said:
I think that simplifies down to p OR q OR r, just from sketching my own Venn diagram.

Actually I think that's wrong. One minute...

I keep getting p AND q OR r.

SlyReaper · 20 Mar 2010 at 21:53

Here we go.

The answer

JC-Retro · 20 Mar 2010 at 21:55

SlyReaper said:
Here we go.

The answer

I actually had the answer written down too. Thanks, that's exactly what I was after, just a nod in the right direction

Amleto · 20 Mar 2010 at 22:01

nm, got it wrong from not paying attention

PeterNem · 20 Mar 2010 at 22:09

Reminds me of my A Level electronics days!! \o/

Artheas · 20 Mar 2010 at 22:17

Wow awesome website!! Would've been useful when in my studying days -.-

gumbald · 20 Mar 2010 at 22:44

I'm impressed someone actually found a use for WA!

digipeep · 20 Mar 2010 at 23:00

Can anyone remember using a Karnaugh map to solve these types of problems. They were great fun as you went into higher dimensions.

I still got a copy of Digital Design by M. Morris Mano. Awesome book if you are starting out in digital electronics.

gumbald · 20 Mar 2010 at 23:02

digipeep said:
Can anyone remember using a Karnaugh map to solve these types of problems. They were great fun as you went into higher dimensions.

I still got a copy of Digital Design by M. Morris Mano. Awesome book if you are starting out in digital electronics.

I'd take a photo of mine, but I can't think where it is.

PeterNem · 20 Mar 2010 at 23:02

Yup, I remember creating Karnaugh maps! Used to love that kind of stuff.

-|ScottFree|- · 20 Mar 2010 at 23:04

Artheas said:
Wow awesome website!! Would've been useful when in my studying days -.-

I have been browsing and using this website for years, and you are right... its amazing how many clever people there are here!!

D D Danneh · 20 Mar 2010 at 23:38

I actually translate stuff like that into a C++ syntax in my head and work it out from there

psd99 · 20 Mar 2010 at 23:44

wow really good website would have loved that to have been live when I was studying.

BigglesPiP · 21 Mar 2010 at 01:53

D D Danneh said:
I actually translate stuff like that into a C++ syntax in my head and work it out from there

Are objects, streams or overloaded functions really necessary here?

I bet the program in your head would compile fine as C.

BigglesPiP · 21 Mar 2010 at 01:57

SlyReaper said:
Here we go.

The answer

**** me Wolfram is getting good: http://www.wolframalpha.com/input/?i=400+miles+per+(50+litres+in+imperial+gallons)