If P is a set of integers and 3 is in P, are all the positive multiples of 3 in P?
a)If x is in P, then x+3 is in P
b)If x is in P then x3 is in P
set P
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the ans according to me should be A but it is given to be C
Can someone explain how?
my reasoning says that
if 3 is in P and x+3 is also in P , then all positive multiples of 3 will be in P.
this is because for both the above conditions to be valid , the value of x should be 0.
where am i faltering?
Can someone explain how?
my reasoning says that
if 3 is in P and x+3 is also in P , then all positive multiples of 3 will be in P.
this is because for both the above conditions to be valid , the value of x should be 0.
where am i faltering?

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you are rightclar wrote:the ans according to me should be A but it is given to be C
Can someone explain how?
my reasoning says that
if 3 is in P and x+3 is also in P , then all positive multiples of 3 will be in P.
this is because for both the above conditions to be valid , the value of x should be 0.
where am i faltering?
A should be the answer.
because if 3 is there in the set then all the multiples must be there
a) SUFF
b)NOT SUFF, because it will depend upon what the set is
it can be {...6,3,0,3}
or it can be the infinite set {...6,3,0,3,6.....}
NOT SUFF
The powers of two are bloody impolite!!
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Why C?
I got E.
If X were 2, then we would get 5 or 1.
If X were 3, then we would get 6 or 3, hence multiple of 3.
I got E.
If X were 2, then we would get 5 or 1.
If X were 3, then we would get 6 or 3, hence multiple of 3.