Question

Write an explicit formula for each sequence. 4,1.5,-1,-3.5, . . . . .

Answer 1

I think the answer is -2.5n + 6.5.

How to work it out:

1. Look at how much it goes down by (since it's going down, put a negative sign)
2. Find out the "0th term". In this case, you would add 2.5 to 4 to find out the 0th term.
3. If the "0th term" is positive, put + … and if its negative, put - …
4. So I think the answer is -2.5n + 6.5