Question

How to find consecutive term ?

Answer 1

you can use a general formula to find any term of an arithmetic sequence. Finding the general formula for the nth term of an arithmetic sequence is easy as long as you know the first term and the common difference.

Find the common difference, d.

To find the common difference, simply subtract one term from the one after it: –4 – (–7) = 3. Thus d = 3.

Plug a1 and d into the general formula for any arithmetic sequence to write the specific formula for the given sequence.

Start with this equation:

an = a1 + (n – 1)d

Then plug in what you know: The first term of the sequence is –7, and the common difference is 3:

an = –7 + (n – 1)3 = –7 + 3n – 3 = 3n – 10

Plug in the number of the term you’re trying to find for n.

To find the 55th term, plug 55 in for n into the general formula for an:

a55 = 3(55) – 10 = 16