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Kapil Gupta

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Aug 25, 2015, 7:30:42 PM8/25/15
to Discrete Mathematics and Logic

Not all girls like all the dog
or
~(\forall g\in G, \forall d\in D, (g,d)\in L)

To solve this we first try to understand negation
what is negation of all girls are beautiful
\forall g\in G g\in B

The negation of this idea is  "this is not the case that all the girls are beautiful" which means "there is atleast one girl who is not beautiful"

~(\forall g\in G, g\in B)

is equivalent to

\exists g \in G, g\notin B)

So, it means that when we negate a sentence
  1.  \forall changes to \exists and vice-versa.
  2. belongingness after quantifier does not change and
  3. the condition after this is negated.

for more examples check following link


http://cwave.eu5.org/kapil/kapil1.html#Negation:%20$\neg$



parul gautam

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Aug 26, 2015, 2:31:26 PM8/26/15
to Discrete Mathematics and Logic
Sir is there any book from which i can get more examples?

Kapil Gupta

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Aug 27, 2015, 6:35:08 PM8/27/15
to Discrete Mathematics and Logic

On Thursday, 27 August 2015 00:01:26 UTC+5:30, parul gautam wrote:
Sir is there any book from which i can get more examples?

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