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Re: If s, u, and v are positive integers and 2s = 2u + 2v, which of the fo
[#permalink]
04 May 2014, 13:23
Hi,
why we can't consider 0 as a value for U - as 0 is a positive integer. If U = 0 then S = V thus option 3 will not hold true.
Following post from tells that we can consider 0 as non-negative integer.
Bunuel Math Expert
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follow send pm Re: PS-which of the following must be true [#permalink] 22 May 2012, 01:23 Expert's post Joy111 wrote:
Bunuel wrote:
LM wrote:
If x and y are integers such that ,and z is non negative integer then which of the following must be true?
A)
B)
C)
D)
E)
Note that we are asked "which of the following MUST be true, not COULD be true. For such kind of questions if you can prove that a statement is NOT true for one particular set of numbers, it will mean that this statement is not always true and hence not a correct answer.
Given: and .
Evaluate each option:
A) --> not necessarily true, for example: and ;
B) --> not necessarily true, for example: and ;
C) --> not necessarily true, if then ;
D) --> not necessarily true, it's true only for ;
E) --> as then and as then --> always true.
Answer: E.
amazing ! couldn't figure out how option 3 was not necessarily true , forgot that non negative could mean that 0 is possible ,folks : non negative does not mean only positive integers , it could be 0 as well
Hypothetically speaking, Bunuel so if a question says, non positive numbers can we consider 0 as well , rather than only negative numbers.
Set of Non positive numbers { 0,-1,-5,-9 }
Set of Non negative numbers { 0,1, 4, 7, }
is this correct?
Yes, a set of non-positive numbers consists of zero and negative numbers.