1. **State the problem:** We have the arithmetic sequence $-18, -23, -28, -33, \ldots$ and need to find the recursive formula, explicit formula, and the 52nd term.
2. **Identify the common difference:** The difference between consecutive terms is $-23 - (-18) = -5$.
3. **Write the recursive formula:** The first term is $a_1 = -18$ and each term is obtained by subtracting 5 from the previous term.
$$a_n = a_{n-1} - 5, \quad a_1 = -18$$
4. **Write the explicit formula:** The explicit formula for an arithmetic sequence is
$$a_n = a_1 + (n-1)d$$
where $d$ is the common difference.
Substitute $a_1 = -18$ and $d = -5$:
$$a_n = -18 + (n-1)(-5)$$
Simplify:
$$a_n = -18 - 5(n-1)$$
$$a_n = -18 - 5n + 5$$
$$a_n = -5n - 13$$
5. **Find the 52nd term using the explicit formula:**
$$a_{52} = -5(52) - 13$$
$$a_{52} = -260 - 13$$
$$a_{52} = -273$$
**Final answers:**
- Recursive formula: $a_n = a_{n-1} - 5$, $a_1 = -18$
- Explicit formula: $a_n = -5n - 13$
- 52nd term: $-273$
Arithmetic Sequence Af1255
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