How do I evaltuate this limit as n goes to infinity?
(n^n)/((n+3)^(n+1))
Please show your working
Thanks, James
(n^n)/((n+3)^(n+1))
Please show your working
Thanks, James
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What if we factor the denominator (n + 3)^(n + 1) as (n + 3)(n + 3)^n ?
Then, our rational expression becomes:
n^n / ((n + 3)(n + 3)^n)
We can write this as the product of two rational expressions:
(n^n / (n + 3)^n) (1 / (n + 3))
Then, we take the product of the two limits:
lim (n^n / (n + 3)^n) lim (1 / (n + 3))
Now, we don't care what the limit of the first term is, as long as it converges (Note: it's 1/e^3), because we know the limit of the second term lim (1 / (n + 3)) = 0 as n -> infinity.
So, the product of the two limits is (something times) 0, and so the limit itself is 0.
Then, our rational expression becomes:
n^n / ((n + 3)(n + 3)^n)
We can write this as the product of two rational expressions:
(n^n / (n + 3)^n) (1 / (n + 3))
Then, we take the product of the two limits:
lim (n^n / (n + 3)^n) lim (1 / (n + 3))
Now, we don't care what the limit of the first term is, as long as it converges (Note: it's 1/e^3), because we know the limit of the second term lim (1 / (n + 3)) = 0 as n -> infinity.
So, the product of the two limits is (something times) 0, and so the limit itself is 0.