Problem 32 on page 630 in Larson Calculus 9e.
In Exercies 29-36, test for convergence or divergence, using each test at least one. Identify which test was used.
32.∞∑n=21n3−8
when n=2 a2=123−8=10 Uh, not possible to divide by zero.
I know it converges for ∞∑n=31n3−8=−13
But what is *Undefined*+−13= ????
From the comments, it is very likely a typo.
Thus, I will present some problems for more clearity.
∞∑n=01n3−8=−13 Will not converge because at n=2 there is singularity?
Aka, No series can converge if there exist a singularity?
Answer
In this case, as many pointed out, it seems like a typo.
Regarding:
Thus, I will present some problems for more clearity.
∞∑n=01n3−8=−13 Will not converge because at n=2 there is singularity?
Aka, No series can converge if there exist a singularity?
Notice that
∞∑n=01n3−8=−13
is just a (no sense) formula, so it cannot converge or diverge.
The question
Does
∞∑k=0ak
converge?
It's a shorthand for
Does the sequence
(n∑k=0ak)n∈N
converge?
In this case
(n∑k=01k3−8)n∈N
doesn't even makes sense, you have already noted why, so it can't converge nor diverge.
No comments:
Post a Comment