14 Replies
iTeachChem Helper
@Apu
iTeachChem Helper
Note for OP
+solved @user1 @user2... to close the thread when your doubt is solved. Mention the users who helped you solve the doubt. This will be added to their stats.
CorrodedCoffin
CorrodedCoffinOP2w ago
only thing i can figure out is writing 1/r+3 as integral x^2r from 0 to 1 @SirLancelotDuLac
SirLancelotDuLac
Ooh this looks fun... Ye, I have an idea: Write the numerator as $\frac{r+3-r}{3}(\text{stuff})$ then $\sum{r=0}^{n} \frac{\binom{n}{r}}{3.n^{r}}-\sum{r=0}^{n}\frac{\binom{n}{r}r}{3.n^{r}(r+3)}$ After this, let the limit be L Then note that as n tends to infinity
TeXit
TeXit2w ago
SirLancelotDuLac
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SirLancelotDuLac
the second term in the expression above tends to L/3 and the first term is (1+1/n)^n/3 So L=e/3-L/3 which means 4L/3=e/3 which means L=e/4? I'm not sure, I'll look at this again if it's incorrect. Though is the answer e/4? @hardcoreisdead
CorrodedCoffin
CorrodedCoffinOP2w ago
e-2
SirLancelotDuLac
Did you ever get an answer to this? If so, can you please share in this thread before closing it?
CorrodedCoffin
CorrodedCoffinOP2d ago
i kinda did
CorrodedCoffin
CorrodedCoffinOP2d ago
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CorrodedCoffin
CorrodedCoffinOP2d ago
i am not sure of step 3 tho
CorrodedCoffin
CorrodedCoffinOP2d ago
No description
SirLancelotDuLac
Gahh I missed that. Step 3 is just limit(a tending to something) integral(expression of x and a).dx is integral of limit of (expression of x and a).dx
CorrodedCoffin
CorrodedCoffinOP2d ago
oh right damn W ques

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