sum the series

sum the series

1+ 1/2 + 1/3 + 1/4..........
i used integration ....but that doesn't help as log {0} doesn't exist .....please help.....please give an explanation with your answer

11 Answers

341
Hari Shankar ·

look up Harmonic Series and its divergence

Perhaps you are looking for:

\lim_{n \rightarrow \infty} \frac{1}{1+n} + \frac{1}{2+n} + ... + \frac{1}{2n}

1
Rohan ·

sorry sir i didn't get harmonic series and its divergence ....
what is it ?

39
Dr.House ·

nice terminology sir.... [156]

1
Honey Arora ·

The given series is 1,1/2,1/3,.....,1/n
Tn=1/n
Sn =∫Tn =∫1/n =log(n)
n>0

24
eureka123 ·

we are looking for
S= x/1 +x2/2 +x3/3 +.............+xn/n

diff. => S' =x+x2+x3+......+xn=(1-xn)/(1-x)

1
=>S=∫1-xn)/(1-x) dx
0

1
Honey Arora ·

if u put x=2 in the 'S' u hv given the ques changes.....
S= x/1 +x2/2 +x3/3 +.............+xn/n

1
Rohan ·

@ honey as n →∞ ...we have log (∞)......we may say =∞
but 1 + 1/2 + 1/3 + ......= ∞ .......isn't something wrong .....all nos. are less than or equal to 1 ......and that too there no. extend upto infinity ,...ie upto zero ......i find something strange
there sum must be finite

24
eureka123 ·

hey rohan....havent u got the answer?????????

341
Hari Shankar ·

@rohan: I will try one more time.

look up wikipedia for harmonic series.

this applies to the other guys who have posted in this thread too

66
kaymant ·

This series is the so called harmonic series. This series diverges (which means that sum to n terms increases as n increases) and hence we cannot sum it.

1
Honey Arora ·

http://demonstrations.wolfram.com/TheSumOfTheHarmonicProgressionAsAnIntegral/

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