Ok, I haven't done maths for a few years now and I've been set the following question:(adsbygoogle = window.adsbygoogle || []).push({});

The sum of the first integers is given by:

Sum(n) = 1+2+3+4 ....... +n = n(n+1)/2

Find similar formulae for

Even(n) = 2+4+6+8 ....... +2n

Odd(n) = 1+3+5+7 ........ +(2n-1)

Now the formulae I have come up with, by trial and error mind, are:

Even = n(n+2)/4

Odd = n(n)/4

Am I on the right lines here? And if so is there a mathematical way of coming up with these formuale that doesn't involve trial and error?

cheers

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# Homework Help: Help with sum of first n integers.

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