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l33t_V
Oct16-09, 02:13 PM
Can someone help me with finding the limit of (x/x+1)^x as x tends to infinity

Mark44
Oct16-09, 02:21 PM
The limit is infinity, unless of course this is what you meant:
\lim_{x \rightarrow \infty} \left ( \frac{x}{x + 1}\right )^x

If you want to write the quotient of x and x + 1, put parentheses around what goes in the denominator, like so: x/(x + 1).

g_edgar
Oct16-09, 02:39 PM
unless of course this is what you meant:
\lim_{x \rightarrow \infty} \left ( \frac{x}{x + 1}\right )^x


The reciprocal is
\lim_{x \rightarrow \infty} \left ( \frac{x+1}{x}\right )^x
Can you do that limit?

l33t_V
Oct16-09, 02:56 PM
The limit is infinity, unless of course this is what you meant:
\lim_{x \rightarrow \infty} \left ( \frac{x}{x + 1}\right )^x

If you want to write the quotient of x and x + 1, put parentheses around what goes in the denominator, like so: x/(x + 1).


Yes, i meant (x/(x+1))^x

l33t_V
Oct16-09, 03:43 PM
Never mind, I solved it.

(x/(x(1+1/x)))^x = (1/(1+1/x))^x = 1^x/(1+1/x)^x where 1^x = 1 and (1+(1/x))^x as x tends to inf = e^1

therefore as x tends to infinity the function tends to e^-1

centry57
Oct18-09, 01:14 AM
\lim_{x\rightarrow \infty} (x/x+1)^x= \lim _{x\rightarrow \infty} (1+\frac{-1}{x+1})^{-(x+1)\frac{x}{-(x+1)}})=\lim_{x\rightarrow \infty} e^\frac{x}{-(x+1)}}=e^{-1}