|
Logic: SD Anyone...anyone?
|
View this Thread in Original format
| biznology |
| Alright, so Im reasonably bright, but I cant ing figure out one of the rules here...how do I get rid of ~ on p when there is no q? Wrong ing day to wait to finish my homework| |
|
|
| biznology |
well perhaps someone does know what im talking about...and you have the right idea. but im ing stuck on how to derive (B v H) from ~(A v ~A)...
the contradiction is obviously in the As, but i cant get them outta that damn ~()...ugh| |
|
|
| Noisician |
~(a ∨ ~a) ≡ ~(t) ≡ c
or you can go by de morgan's and get
~(a ∨ ~a) ≡ ~a ∧ a ≡ c
is that what you need? elaborate plz. |
|
|
| biznology |
| Uhh its not SD+ so n DeM...but i think i figured it out| |
|
|
| caddyshack |
| quote: | Originally posted by Noisician
~(a ∨ ~a) ≡ ~(t) ≡ c
or you can go by de morgan's and get
~(a ∨ ~a) ≡ ~a ∧ a ≡ c
is that what you need? elaborate plz. |
:conf:
i motion for a TA homework forum |
|
|
| Noisician |
| quote: | Originally posted by biznology
Uhh its not SD+ so n DeM...but i think i figured it out| |
oh you said sd... n/m then, i'm blind :stongue: |
|
|
| Dr. Cfire |
| quote: | Originally posted by biznology
well perhaps someone does know what im talking about...and you have the right idea. but im ing stuck on how to derive (B v H) from ~(A v ~A)...
the contradiction is obviously in the As, but i cant get them outta that damn ~()...ugh| |
try negated disjunction decomposition
~(A v ~A)
---------
~A
~~A
A&~A -contradiction |
|
|
| SuperFarStucker |
| I nominate Noisician as TA mathematical and coding genius! That guy can answer any question :p |
|
|
| biznology |
| quote: | Originally posted by Dr. Cfire
try negated disjunction decomposition
~(A v ~A)
---------
~A
~~A
A&~A -contradiction |
ah that makes sense, but its too late now. but at least I get it now. never shoulda taken that class| |
|
|
|
|
