To find the nth term of the arithmetic sequence 15, 6, 3, 12, we first need to identify the common difference and the first term.
The common difference (d) is the difference between consecutive terms. Let’s calculate that:
- 6 – 15 = -9
- 3 – 6 = -3
- 12 – 3 = 9
Here, we can see that the differences are not consistent, which indicates that this sequence is not an arithmetic sequence. It appears the order of terms may be incorrect.
However, for educational purposes, if we were to analyze typically an arithmetic sequence, we would take the first term (a) and the common difference (d) into account to find the nth term.
If we assume these numbers are supposed to be in an arithmetic sequence, we’d need consistent differences. If we corrected the sequence or re-evaluated, we could then use the formula:
an = a + (n – 1)d
Where:
- a = first term
- d = common difference
- n = term number
In a proper arithmetic sequence, you could plug in the values you find for a and d into the formula to find the nth term.