If the fourth term in a geometric sequence is –1 and the common ratio is –1, find the explicit formula of the sequence.
Question 15 options:

A)

an = (1) ⋅ (–1)n – 1 for n ≥ 1

B)

an = (– 1) ⋅ (1)n – 1 for n ≥ 1

C)

an = (1) ⋅ (1)n – 1 for n ≥ 2

D)

an = (–1) ⋅ (–1)n – 1 for n < 1

it's both, now can you answer my most recent question?

think about the doctor who treated the major and the speaker in the short story "in another country." put yourself in the shoes of the doctor, and based on what you read in the story, write what you think his thoughts about the major and the speaker would be. use the following vocabulary in your response and change the form of these words as needed: detached resign withered

a_n = a_1 + (n - 1)d

the first term is 6.

the common difference d = ?

when you find d, replace n with 7 and d with the common difference to find your answer.