Remember when I did that list with the a's to describe a sequence...
And I told you this was the nth term?
That probably didn't mean much to you at the time. Here's what we use this for:
The nth term is given by a formula.
We can use this formula to build the sequence.
Check it out:
Let's build the sequence whose nth term is given by
See the n's in this guy ?
If we let n = 1, we'll get the first term of the sequence:
If we let n = 2, we'll get the second term:
If we let n = 3, we'll get the third term:
and so on...
So, our sequence is
When you're given a formula for , you stick in n = 1, then
n = 2, then 3, 4, and 5 to get the first five terms.
Build the sequence (the first five terms) whose nth term is given by