What is the Limit of (1+x)^(1/x) as x approaches 0?

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In summary: Then you can use the Fundamental Theorem of Calculus to evaluate the limit.In summary, the conversation discusses solving a problem involving limits and logarithms. The speaker suggests using l'Hopital's rule and hints at using the Fundamental Theorem of Calculus to evaluate the limit. The original poster also mentions trying different options and asking for help with using WolframAlpha.
  • #1
vkash
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1

Homework Statement



see attachment

Homework Equations



limx->0(1+x)1/x=e

The Attempt at a Solution


step 1: take log in both sides of an=...(as in function).
step 2: multiply and divide it by 2n inside the log.
step 3: there are n terms in multiplication so substitute 2(of denominator ) with all of the terms.
on solving it comes out to be ln2. which is equal to limn->infln an so final answer will 2.
I solve all the options but none of them give 2.
can you please tell me where am i doing it wrong.
OR
how to know it's answer on wolframalpha. Since i don't know proper commands to do it
 

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  • #2
The log is (1/x)*log(1+x). I would just use l'Hopital's rule from there. I don't see where step 2 is going.
 
  • #3
Dick said:
The log is (1/x)*log(1+x). I would just use l'Hopital's rule from there. I don't see where step 2 is going.
you are solving relevant equation not the question i raised.
see attachment.
 
  • #4
vkash said:
you are solving relevant equation not the question i raised.
see attachment.

Of course, sorry.
 
  • #5
Ok, so taking the log gives you log(1/n)+(1/n)*(log(2n+1)+...+log(2n+n)), ok so far? Now log(1/n)=(1/n)*n*log(1/n)=(1/n)*(log(1/n)+log(1/n)+...+log(1/n)). Add the two sums together and interpret it as a Riemann sum. Sorry to not be more accurate in notation here, but this is along the lines of a hint.
 
  • #6
Dick said:
Ok, so taking the log gives you log(1/n)+(1/n)*(log(2n+1)+...+log(2n+n)), ok so far? Now log(1/n)=(1/n)*n*log(1/n)=(1/n)*(log(1/n)+log(1/n)+...+log(1/n)). Add the two sums together and interpret it as a Riemann sum. Sorry to not be more accurate in notation here, but this is along the lines of a hint.

doesn't understand>:confused:
 
  • #7
vkash said:
doesn't understand>:confused:

Well, I don't understand how you got ln2 either. If you can show that in more detail maybe someone can tell you why it's wrong. I'm suggesting to write out the sum you get from the log in such a way that it looks like a Riemann sum for an integral.
 

FAQ: What is the Limit of (1+x)^(1/x) as x approaches 0?

What is a limit in calculus?

A limit in calculus represents the value that a function approaches as the input value gets closer and closer to a specific number. It is denoted by the notation "lim f(x) as x approaches a."

How do you solve a limit?

To solve a limit, you can use various methods such as direct substitution, factoring, rationalization, or using trigonometric identities. You can also use L'Hopital's rule or graphing to find the limit.

What are the rules for solving limits?

The main rules for solving limits include the limit laws, which state that the limit of a sum, difference, product, or quotient of two functions is equal to the sum, difference, product, or quotient of their individual limits. Other rules include the Squeeze Theorem, L'Hopital's rule, and the Intermediate Value Theorem.

What is the difference between a one-sided limit and a two-sided limit?

A one-sided limit only considers the values of the function as the input value approaches the limiting value from one side (either the left or the right). A two-sided limit considers the values from both sides and requires that the function approaches the same value from both sides to exist.

Can a limit not exist?

Yes, a limit may not exist if the function has a vertical asymptote, a hole, or an infinite oscillation at the limiting value. In these cases, the limit is said to be undefined or does not exist.

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