Integer

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Integer

by govind_raj_76 » Sun Jun 13, 2010 1:18 pm
If m is an integer, which of the following is always true ?

1) m^2 - 1 is non - negative.

2) m(m + 1) is divisible by 3.

3) m(m ^ 2 + 1) is divisible by 4.

4) m^2 when divided by 3 leaves remainder 0 or 1 (but never 2).

5) If m < 0, then -m < - m^2

Please help in solving this problem.
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by tpr-becky » Sun Jun 13, 2010 2:02 pm
This is best done by pluggin in numbers -


most of them can be proven incorrect by using 1 as m - but when it comes to #4 - you can pick numbers all day long as still get that it works.

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by odod » Sun Jun 13, 2010 2:21 pm
but if m=0 or m=1 for statement 4, then we get a remainder of 3 and 2 respectively. So statement 4 doesn't work. right?
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by sogmat » Sun Jun 13, 2010 4:47 pm
if m=0 then remainder = 0
if m=1 then remainder = 1

4 is the right answer