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versatile801
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Number properties

by versatile801 Thu Dec 29, 2011 4:17 pm

Hi,

The question pertains to Number Properties. ( pg no 153, Q-5 )

what are the remainders upon division by 4 ?

Option B - the square of an ODD integer

Answer is - 1

Now the answer explanation says that Generic expression of an odd integer is 2n+1.

If we consider the above definition to suppose an odd number , we are missing 1 - which is an odd no itself.

In the same question, if i take odd no as 1 , the square of this odd no is 1 , and when divided by 4, it leaves 0 reminder

Pls explain, why generic expression of odd no is taken as 2n+1 ?
tim
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Re: Number properties

by tim Sat Dec 31, 2011 1:50 pm

How do you get an odd number? It’s one more than an even number. An even number is twice an integer, in other words 2n; so an odd number is 2n+1..
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versatile801
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Re: Number properties

by versatile801 Sat Dec 31, 2011 11:50 pm

Thanks tim.

But what about 1 then.. ??

1 is also odd no, it does not require 2n to be added to it, when we say 2n+1, it starts with no 3 and goes on.

So, how can we say generic expression of an odd no is 2n+1 ?

thanks
stud.jatt
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Re: Number properties

by stud.jatt Wed Jan 04, 2012 8:16 pm

versatile801 Wrote:Thanks tim.

But what about 1 then.. ??

1 is also odd no, it does not require 2n to be added to it, when we say 2n+1, it starts with no 3 and goes on.

So, how can we say generic expression of an odd no is 2n+1 ?

thanks


umm... lets try n = 0 shall we??
tim
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Re: Number properties

by tim Tue Jan 10, 2012 3:55 pm

Thanks, stud [sic]
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