Integrate using what!
∫ 0 ∞ x 9 ( e x + 1 ) 5 e x ( 1 1 e x − 1 1 e 2 x + e 3 x − 1 ) d x
The value of above integral is equal to B A π C where A , B , C ∈ Z and A , B are co-prime integers.
Find A × ( B + C )
Original problem
The answer is 2604.
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1 solution
@Upanshu Gupta plz check it out
@Tanishq Varshney the mistake you made in realizing that Γ ( n ) = ( n + 1 ) ! is wrong so the integral should equal 9 ! not Γ ( 7 ) but Γ ( 1 0 ) equalling 9!
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@Tanishq Varshney rest I did the same!
It's ( n − 1 ) ! my friend
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@Tanishq Varshney you know it's confusing!! but I even wolfram alpha(ed) the integral: ∫ 0 ∞ x 9 e − x d x = 9 ! = 3 6 2 8 8 0
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@Kunal Gupta – Ya u are right , I got screwed up. @Calvin Lin sir plz change the answer
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@Tanishq Varshney – @Tanishq Varshney finally ! victory!! :P
@Tanishq Varshney – @Tanishq Varshney btw my name's changed (3 years back) to Kunal Gupta but I can't change it on Brilliant
@Tanishq Varshney I think you should ask @Calvin Lin to change the answer to 2 6 0 4
Shouldn't you update the solution likewise?