can someone show me hot to evaluate this
its the sum of numbers generated from 0 to n-1
why from zero, its from 1
k=1; but the first term is 1-1 = 0
so what is the process to evaluate this
when k=n; you get the nth number as n-1
what do you mean by "evaluate"? thats a pretty vague term
how do i get the answer
.... depends on what kind of an answer a person is looking for.
i looking for this answer: (n^2-n)/(2)
ok , a formula fir the sum ... thats better
lets write out what we know about the series A = {0 + 1 + 2 +... + (n-3) + (n-2) + (n-1)} if we add this to itself we get: A = {0 + 1 + 2 +...+ (n-3) + (n-2) + (n-1)} + A = {{n-1) + (n-2) + (n-3)+...+ 2 + 1 + 0 } ------------------------------------------------- 2A = {(n-1) + (n-1) + (n-1) +...+ (n-1) + (n-1) + (n-1)} which reduces to: 2A = n(n-1) A = n(n-1)/2
n(n-1) (n^2-n) ----- = ------- 2 2
Does that make sense?
sure does, but i found it a different way
all roads lead to rome, except for the one on the left :)
no, all roads dont lead to rome
whoever told you that is wrong
lets try this. the formula for \[\sum_{k=1}^n k = \frac{n(n+1)}{2}\] and \[\sum_{k=1}^n 1=n\] so you can compute \[\frac{n(n+1)}{2}-n\] for your answer
right thank you, that was the way i did it too
whew!! good thing sate came along and gave us the right way to do it ... ;)
yeah, good thing you suck
now that was uncalled for.
no, your smart *** reply was uncalled for and you know it
you appear to be misinterpreting my response ... but whatever, I gave sate props for his reply.
yeah, yeah sure thats what you did
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