Tuesday, November 16, 2010

 TEAM 13

1)      If statement q has the truth value 1, determine all truth value assignments for the primitive statements p,r and s for which the truth value of the statement
           (q -> [ (~p V r) ^ ~s ] )  ^  [ ~s -> ( ~r ^ q ) ]    is 1
P
r
s
~p
~pVr
~s
(~pvr)^~s
q-> [(~pvr)^~s]
~r
~r^q
~s-> (~r^q)
[q->((~pvr)^~s)]-> [~s->(~r^q)]
1
1
1
0
   1
0
0
       0
0
   0
          1
            0
1
1
0
0
   1
1
1
       1
0
   0
          0
            0
1
0
1
0
   0
0
         0
       0
1
   1
          1
            0
1
0
0
0
   0
1
         0
       0
1
   1
          1
            0
0
1
1
1
   1
0
         0
       0
0
   0
          1
            0
0
1
0
1
   1
1
         1
       1
0
   0
          0
            0
0
0
1
1
   1
0
         0
       0
1
   1
          1
            0
0
0
0
1
   1
1
         1
       1
1
   1
          1
            1






From  the  above  truth  table ,
P=0,  r=0 and s=0
                               
 

2) Verify that       [ (p<->q) ^ (q<->r) ^ (r<->p) ] ó [ (p->q) ^ (q->r) ^ (r->p) ]

p
Q
r
P<->q
q<->r
r<->p
(p<->q)^(q<->) ^(r<->p)
p->q
q->r
r->p
(p->q)^(q->r)^(r->p)
1
1
1
    1
   1
   1
        1
   1
  1
1
1
1
1
0
    1
   0
   0
        0
   1
  0
1
0
1
0
1
    0
   0
   1
        0
   0
  1
1
0
1
0
0
    0
   1
   0
        0
   0
  1
1
0
0
1
1
    0
   1
   0
        0
   1
  1
0
0
0
1
0
    0
   0
   1
        0
   1
  0
1
0
0
0
1
    1
   0
   0
        0
   1
  1
0
0
0
0
0
    1
   1
   1
        1
   1
  1
1
1

By comparing column no 7 and 11, we can say that
[ (p<->q) ^ (q<->r) ^ (r<->p) ]  ó  [ (p->q) ^ (q->r) ^ (r->p) ]

3) let p (x,y) , q (x,y) denote the following open statement,
p (x,y) :  x² ≥ y
q (x,y) : x+2 < y
if the universe for each of x , y consists of all real numbers , determine the truth value for each of the following statements.
è
Given : p (x,y) :  x² ≥ y
             q (x,y) : x+2 < y
where   x , y €  R.

A)  p (2,4)
è  2² ≥ 4 
       i.e  4 = 4
       .’. P (x,y) IS TRUE.

B) q(1,Π )
è 1+2 < Π
      i.e  3<Π
 .’. q (1,Π ) IS TRUE .            [ ‘.’ Π=3.142]

C)  p (-3 ,8 ) ^ q (1 ,3)
è  ((-3)² ≥ 8) ^ (1+2 < 3)
       (9≥8)  ^   (3<3)
       TRUE   ^   FALSE
  .’. FALSE

D) p (1/2 ,1/3)  V  ~q (-2 ,-3)
è  (1/4 ≥ 1/3)  V  (~ ( -2 + 2 < -3))
       FALSE     V     ~ ( FALSE )
       FALSE    V   TRUE
   .’.  TRUE.

E) p ( 2,2 )àq ( 1,1 )
è  (4 ≥ 2)à (3 < 1)
       TRUEàFALSE
    .’. FALSE.

F) p (1 ,2)ßà (~ q(1 ,2))
è  (1 ≥ 2)ßà(~ ( 3 < 2 ))
       FALSE ßà (~( FALSE))
       FALSE ßà TRUE
   .’. FALSE








4)
a) how many sub sets of {1,2,3,……11} contains at least one even integer.

b) how many sub sets of {1,2,3,……12} contains at least one even integer.

c) generalize the results of part (a) and (b)

è
We know that ,
Number of sub sets of a set X is given by 2ⁿ.
Where ‘n’ is the number of elements in X.  i.e  n = |X|.

 a)  let A={1,2,3,…….11}
      here |A| = 11,
     ,’. Total Sub sets of A = 2¹¹
                                                     = 2048.

Now considering only odd integers in A,
  |A|(odd)=6
 .’. Sub sets of odd integers of A = 64

.’. sub sets containing at least one even integer is given by
   A(even) = total sub sets of A – sub sets with only odd integers
                     = 2048 – 64
                     = 1984.
                 
b)  let B={1,2,3,…….12}
      here |B| = 12,
     ,’. Total Sub sets of B = 2¹²
                                                     = 4096.

Now considering only odd integers in B,
  |B|(odd)=6
 .’. Sub sets of odd integers of B = 64

.’. sub sets containing at least one even integer is given by
   B(even) = total sub sets of B – sub sets with only odd integers
                     = 4096 – 64
                     = 4032.
                 


c) In general let the number of even integers in the given set be n then,
If n is even, then
   total number of  sub sets contains at least one even integer.=[2n-2n/2]
If n is odd, then
   total number of  sub sets contains at least one even integer.=[2n-2(n+1)/2]


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