1. **Problem Statement:** Find the general term, the 10th term, and the first three terms of an arithmetic progression (A.P.) where the first term $a_1=4$ and the common difference $d=-5$.
2. **Formula for the general term of an A.P.:**
$$a_n = a_1 + (n-1)d$$
where $a_n$ is the $n^{th}$ term, $a_1$ is the first term, and $d$ is the common difference.
3. **Calculate the general term:**
Substitute $a_1=4$ and $d=-5$ into the formula:
$$a_n = 4 + (n-1)(-5) = 4 - 5(n-1) = 4 - 5n + 5 = 9 - 5n$$
4. **Find the 10th term:**
Substitute $n=10$ into the general term:
$$a_{10} = 9 - 5(10) = 9 - 50 = -41$$
5. **Find the first three terms:**
- For $n=1$: $$a_1 = 9 - 5(1) = 9 - 5 = 4$$
- For $n=2$: $$a_2 = 9 - 5(2) = 9 - 10 = -1$$
- For $n=3$: $$a_3 = 9 - 5(3) = 9 - 15 = -6$$
**Final answers:**
- General term: $$a_n = 9 - 5n$$
- 10th term: $$a_{10} = -41$$
- First three terms: $$4, -1, -6$$
Ap General Term
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