I don't understand your approach for the first argument:
If the result muss be odd, so x must be even. It will be even if x is 2 or greater than 2. If x is odd the result won't be odd. If I say x = 1 so the result will be Zero. But Zero is neither even nor odd. So the satetement is sufficient ?
--> so 2x=even
. Hence 2x-1=odd
just means that x
is an integer (it can be even as well as odd).
2. If x=1
the result wont be zero, it'l be 1, so odd: 2*1-1=2-1=1=odd
3. Zero is an even integer
. Zero is nether positive nor negative, but zero is definitely an even number.
An even number is an integer
that is "evenly divisible" by 2, i.e., divisible by 2 without a remainder and as zero is evenly divisible by 2 then it must be even (in fact zero is divisible by every integer except zero itself).
Or in another way: an even number is an integer
of the form n=2k
, where k
is an integer. So for k=0
Hope it's clear.
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