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Evaluate the integral above. Take ζ ( 2 3 ) = 2 . 6 1 2 .
Extra Credits:
Find a general solution to the problem.
The first person who posts the solution explaining all the steps wins my respect.
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Elegant solution :)
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I didn't even understand the solution!Swapnil!
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Which part u didn't understand?
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@Aditya Kumar – Actually I am not aware of Ramanujan Master Theorem and those integrals which involve gamma function.
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@Adarsh Kumar – Hmm. Try learning them
You don't need to understand everything to feel the beauty of Mathematics.
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@Swapnil Das – True,but to understand this particular solution i need to.:P
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@Adarsh Kumar – Then read up the part you didn't understand.
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@Swapnil Das – Actually then Swapnil I would have to start and stop at the beginning :P!lolol
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@Adarsh Kumar – Do you know limits and derivatives?
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@Swapnil Das – Yes,but i don't know gamma function and zeta function.
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@Adarsh Kumar – Then, why don't you read integration ?
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@Swapnil Das – That also involves gamma function,sorry.
@Swapnil Das – SD u type really well.
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@Aditya Kumar – Erm.. Thanks. Did you appreciate my typing speed, my way of typing letters or the style of my writing?
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@Swapnil Das – U write really well. Your dialogues are really awesome :P
I know the proof of Ramanujan Nested theorem
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Yeah even I know that:). How was the problem? Did u use rmt?
It also involves his famous taxicab number 1729 :) Nice solution.
Try to prove the radical then you'll win my respect.
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I read many PDFs for its proof , all of them stated to consider some function and then it was easy to go after it.
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Yes u r right.
Hi Tanishq are you going on 15th or 16th
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@Department 8 – what do u mean by that , sorry i didn't understand?
I know the proof.. If you too know ?? Then I don't need to post that :)
I solved it. @Aditya Kumar What do you want to generalise .. What tanishq gave ..are you satisfied with that ?
The answer is = 3 2 π ζ ( 2 3 )
U didn't win my respect :P. Please post the complete solution.
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As the question is a tribute to Sir Ramanujan, the question involves two things related to him.
1 ) N e s t e d R a d i c a l equation 26
2 ) Ramanujan Master Theorem
x + n + a = a x + ( n + a ) 2 + x a ( x + n ) + ( n + a ) 2 + . . . . .
It would be nice if someone provides the proof for this because i don't know :P
Here n = a = 1 7 2 9
Also
ln ( Γ ( 1 + x ) ) = − γ x + k = 2 ∑ ∞ ( k ) ζ ( k ) ( − x ) k
ln ( Γ ( 1 + x ) ) = − γ x + k = 0 ∑ ∞ ( k + 2 ) ζ ( k + 2 ) ( − x ) k + 2
For Proof see Problem number 7 at the last.
→ x 2 ln ( Γ ( 1 + x ) ) + γ x = k = 0 ∑ ∞ ( k + 2 ) Γ ( k + 1 ) ζ ( k + 2 ) k ! ( − x ) k
Thus the integral now becomes
∫ 0 ∞ ( x + 1 7 2 9 + 1 7 2 9 − 3 4 5 8 ) − 2 1 x 2 ln ( Γ ( 1 + x ) ) + γ x d x
= ∫ 0 ∞ x − 2 1 x 2 ln ( Γ ( 1 + x ) ) + γ x d x
Now ϕ ( k ) = ( k + 2 ) Γ ( k + 1 ) ζ ( k + 2 )
thus by Ramanujan Master theorem
= ∫ 0 ∞ x s − 1 x 2 ln ( Γ ( 1 + x ) ) + γ x d x = Γ ( s ) ϕ ( − s )
= ∫ 0 ∞ x s − 1 x 2 ln ( Γ ( 1 + x ) ) + γ x d x = 2 − s Γ ( s ) Γ ( 1 − s ) ζ ( 2 − s )
here s = 2 1
Thus we have by euler reflection formula
= ( 2 − 2 1 ) sin ( 2 π ) π ζ ( 3 / 2 )
3 2 π ζ ( 3 / 2 ) = 5 . 4 6