Answer:
you cant use brainly for tests
Step-by-step explanation:
Answer:
The equation does not match the form of any conic section.
Not a Conic Section
Step-by-step explanation:
Given:
The geometric sequence is:

1 -4
2 20
3 -100
To find:
The explicit formula and list any restrictions to the domain.
Solution:
The explicit formula of a geometric sequence is:
...(i)
Where, a is the first term, r is the common ratio and
.
In the given sequence the first term is -4 and the second term is 20, so the common ratio is:



Putting
in (i), we get
where 
Therefore, the correct option is B.
. The series is divergent. To see this, first observe that the series ∑ 1/kn for n = 1 to ∞ is divergent for any integer k ≥ 2.
Now, if we pick a large integer for k, say k > 100, then for nearly all integers n it will be true that 1 > cos(n) > 1/k. Therefore, since ∑ 1/kn is divergent, ∑ cos(n)/n must also be divergent The *summation* is divergent, but the individual terms converge to the number 0.<span>by comparison test since cosn/n <= 1/n is convergent
and 1/n is divergent by harmonic series
so the series is conditionally converget </span>
Answer:12,16
Step-by-step explanation: