Question

How do you determine whether the sequence `a_n=(-1)^n/sqrtn` converges, if so how do you find the limit?

Answer 1

Limit is 0

Explanation:

`0 <= abs((-1)^n/sqrt(n)) = 1/sqrt(n)`

But `lim_{n to oo} sqrt(n) = + oo`, therefore `lim_{n to oo} 1/sqrt(n) = 0`.

Now, use the theorem of comparison to conclude.