1thank you
Prove:
1/(n+1) + 1/2(n+1)2 + 1/3(n+1)3 = 1/(n) - 1/2(n)2 + 1/3(n)3
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7 Answers
62This is a very interesting problem...
Not very easy to say the least!!
RHS is ln(1+1/n) = ln((1+n)/n)
= - ln(n/(n+1))
= -ln(1-1/(n+1))
= LHS!!! (See carefully u will understand what i am saying :)
1But i felt this was very tough.. it took me 5 minutes to understand what u have written.. specially the LHS
1areeeeyyyyy wow!!
but bhaiya.... how did u know this way u can prove it???......it was a wonderful proof!!!!!
hey we can also prove this by dat all-time popular bachcha-method... MATHEMATICAL INDUCTION....
62haha.. pure coincidence :)
Actually took me sometime to get this one :)
62basically
1/(n) - 1/2(n)2 + 1/3(n)3+ ............
part clicked to me first... it seemed obvious after a second....
but the first side took some time to prove!
even that i tried using something of
ln(1+k) =.. and it just stuck my head :)