The problem asks to find $u_{50}$ and $S_{50}$ for an arithmetic sequence given that $u_2 = 6$ and $u_{10} = 22$. Here, $u_n$ represents the nth term and $S_n$ represents the sum of the first n terms of the arithmetic sequence.
2025/4/3
1. Problem Description
The problem asks to find and for an arithmetic sequence given that and . Here, represents the nth term and represents the sum of the first n terms of the arithmetic sequence.
2. Solution Steps
First, recall the formula for the nth term of an arithmetic sequence:
, where is the first term and is the common difference.
We are given that and . Therefore:
(1)
(2)
Subtract equation (1) from equation (2):
Substitute into equation (1):
Now that we know and , we can find :
Next, we need to find the sum of the first 50 terms, . Recall the formula for the sum of the first n terms of an arithmetic sequence:
Therefore,