What is the 30th term of the arithmetic series 2, 5, 8, … ?

1 Answer
Nov 14, 2015

Answer:

#89#

Explanation:

One way to tackle this would be to count up all the way to the 30th term.

The more elegant way would be to create a linear equation, where #f(x)# is the number in the sequence and #x# is the term number.

We can see that the arithmetic sequence rises by #3# each term, so #3# is our slope. We also know that the first term is #2# (when #x=1#), so we can figure out that our equation must be #f(x)=3x-1#.

With this, we can plug in #30# for #x# and get #color(red)(89)#.