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\[\begin{array}{ccccc}\phi & \neg \phi & \psi & \phi \Rightarrow \psi & \neg \phi \vee \psi \\ \hline \\T&F&T &T&?\\T&F&F&F&?\\F&T&T&T&?\\F&T&F&T&?\end{array}\]
 one year ago
 one year ago
\[\begin{array}{ccccc}\phi & \neg \phi & \psi & \phi \Rightarrow \psi & \neg \phi \vee \psi \\ \hline \\T&F&T &T&?\\T&F&F&F&?\\F&T&T&T&?\\F&T&F&T&?\end{array}\]
 one year ago
 one year ago

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UnkleRhaukusBest ResponseYou've already chosen the best response.2
i think i made a mistake in the table already
 one year ago

RedPrinceBest ResponseYou've already chosen the best response.0
¬ϕ∨ψ means if either ¬ϕ is true or either ψ is true or both are true then the answer is true otherwise it is false ¬ϕ is false but ψ is true so the answer is true, and so on
 one year ago

RedPrinceBest ResponseYou've already chosen the best response.0
post your question again and right!!
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
\[\begin{array}{ccccc}\phi & \neg \phi & \psi & \phi \Rightarrow \psi & \neg \phi \vee \psi \\ \hline \\T&F&T &T&T\\T&F&F&F&F\\F&T&T&T&T\\F&T&F&T&T\end{array}\] is that right?
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
it makes sense now, your answer form before , was right for the table i posted originally
 one year ago

RedPrinceBest ResponseYou've already chosen the best response.0
last one is wrong one of ψ and ¬ϕ is true, so how can it be true.....!!! check this! http://www.hermit.cc/teach/ho/dbms/optable.htm
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
hmmm It seems to be that you are correct Unkle
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
I cant seem to find where you went wrong. Everything seems correct
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
cool, what about this one \[\begin{array}{cccccc}\phi & \psi & \neg\psi & \phi \Rightarrow \psi & \phi \not\Rightarrow \psi &\psi\wedge\neg\psi\\ \hline \\T&T &F&T&\\T&F&T&F&\\F&T&F&T&\\F&F&T&T& \end{array}\]
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
The last column is obv false
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
I am not sure what that sign is of the second to last column
 one year ago

satellite73Best ResponseYou've already chosen the best response.0
You were correct above, proving that the statements are logically equivalent
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
dw:1348840677936:dw
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
phi does not imply psi
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
hmmm Y have I never come across that one????? Ok Let me go get my book and see
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
Well isnt that then the same as ~(P>Q) I mean it should just be the opposite of the column before
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
\[\begin{array}{cccccc}\phi & \psi & \neg\psi & \phi \Rightarrow \psi & \phi \nRightarrow \psi &\phi\wedge\neg\psi\\ \hline \\T&T &F&T&\\T&F&T&F&\\F&T&F&T&\\F&F&T&T& \end{array}\]
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
waitttt we didnt finish the previous one lol
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
is \[\phi\nRightarrow\psi\] the same as \[\neg\phi\Rightarrow\psi\]?
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
\(\neg(\phi\Rightarrow\psi)\)
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
cuz idk I remember doing this stuff and we never came across that symbol
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
ok so you were right\[\phi\nRightarrow\psi\]\[\downarrow\]\[\neg(\phi\Rightarrow\psi)\]\[\downarrow\] opposite to the previous column,
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
The last column is F T F F
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
\[\begin{array}{cccccc}\phi & \psi & \neg\psi & \phi \Rightarrow \psi & \phi \nRightarrow \psi &\phi\wedge\neg\psi\\ \hline \\T&T &F&T&F&F\\T&F&T&F&T&T\\F&T&F&T&F&F\\F&F&T&T&F&F \end{array}\]
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
how did you get the last column ?
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
Ok well that is known as the and connective And the rule there is that a true with False=False A false with a fasle is false and a true with a true =true And it should make sense logically in your brain FALSE AND FALSE=FALSE TRUE AND FALSE cant be true it must be FALSE TRUE AND TRUE is obv TRUE
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
i dont think i understand the difference between ¬φ ∨ ψ these φ ∨ ¬ψ
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
Ok well firstly the connective is the or connective and its always true except when both compartments are false So TRUE OR TRUE=TRUE TRUE OR FALSE=TRUE Lets take the sentence I went to bed early or i went to bed on time Its true statement even though one half of the sentence contradicts the other FALSE OR FALSE+FALSE
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
FALSE OR FALSE=FALSE
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
The only difference is which column you will use.
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
Like one phi is negative and the other psi is negative
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
Well basically if you dont understand the difference then you are basically not following how truth tables are formed
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
ok lets make a truth table.
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
dw:1348842795418:dw
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
This drawing board was def testing my patience
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
the way i figured out the last 2 columns was look at the appropriate 2 columns and decide if it would be true or false
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
YES that table makes sense now thankyou ! @swissgirl
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
lol I hope so. Its kinda hard to explain but if you start from the wayyyyyy begginning then like once you get it its simple
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
i guess we can conclude that \[\phi\Rightarrow\psi\qquad\leftrightarrow\qquad\neg\phi\vee\psi\] and \[\phi\nRightarrow\psi\qquad\leftrightarrow\qquad\phi\vee\neg\psi\]
 one year ago

swissgirlBest ResponseYou've already chosen the best response.1
I dont like the second part of your conclusion Are you sure that it is correct?
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
oh yeah i got that a wrong
 one year ago

UnkleRhaukusBest ResponseYou've already chosen the best response.2
\[\phi\nRightarrow\psi\qquad\leftrightarrow\qquad\phi\wedge\neg\psi\]
 one year ago
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