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earth@work
- Master | Next Rank: 500 Posts
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1/(1*2) = 1 - 1/2
1/(2*3) = 1/2 - 1/3
1/(3*4) = 1/3 - 1/4 and so on
So, we have:
(1 - 1/2) + (1/2 - 1/3) + (1/3 - 1/4) + (1/4 - 1/5)....
Irrespective of whether n is even or odd, you have:
S = (1 - 1/2) + (1/2 - 1/3) + .... + (1/n - 1/(n+1))
= 1 - 1/(n+1) ( notice how the terms cancel each other)
= n/(n+1)
earth@work wrote:how do we find the sum of n terms of series : (1/(1*2)) + (1/(2*3)) + (1/(3*4)) + .........
(not a multiple choice question)
Answer : [spoiler]n/(n+1)[/spoiler]
