Question

The formula for any arithmetic sequence is an = a1 + d(n - 1), where an represents the value of the nth term, a1 represents the value of the first term, d represents the common difference, and n represents the term number. What is the formula for the sequence -1, -5, -9, ...?

an = -1 + 4( n - 1)
an = -1 + (-4)( n - 1)
an = 4 + (-1)( n - 1)
an = -4 + (-1)( n - 1)

Answer 1

Answer: The correct formula for the sequence -1, -5, -9, ... is an = -4 + (-1) n - 1). This formula uses the common difference of -4 and the first term of -1 to calculate the value of the nth term in the sequence.