#Difficult limit problem calculus

19 messages · Page 1 of 1 (latest)

terse dove
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Need to solve it using l'hospital btw

runic pasture
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$e^{\lim_{t\to\infty}t\ln\left(1-\frac{3}{t}\right)}$

hybrid iceBOT
runic pasture
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now, find the limit of the exponent

terse dove
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Can you just take the log of a limit and it remains the same?

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Confused how you did that

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Oh wait, it is e raised to the limit

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Thats really weird, let me see if I can figure that out though

runic pasture
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e^(ln(x))=x

terse dove
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Thanks for the help @runic pasture !

timber kestrelBOT
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@terse dove has given 1 rep to @runic pasture

boreal vortex
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if lim_x->c g(x)=G, then lim_x->c f(g(x))= lim_x->G f(x) = L

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So if f is continuous at L, L = f(G). In this specific example f would be e^t and g would be tln(1+1/t)

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This is a very powerful result with limits and is worth spending time on understanding

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@terse dove

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As for how to evaluate the new limit, tln(1+1/t) is the same as ln(1+1/t)/(1/t)

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Evaluating this at infinity gives you 0/0 so lhoptials rule is applicable