Let's use the formula for the nth term of an arithmetic sequence: an = a1 + (n-1)d, where an is the nth term, a1 is the first term, n is the position of the term, and d is the common difference.
We are given that a128 = -5, a1 = 31, and n = 128. We need to find d.
Using the formula, we can substitute the given values: -5 = 31 + (128-1)d.
Simplifying the equation, we have: -5 = 31 + 127d.
Subtracting 31 from both sides, we get: -36 = 127d.
Dividing by 127, we find: d ≈ -0.2835.
Therefore, the common difference of the arithmetic sequence is approximately -0.2835.
The 128th terms of a AP is -5 find its common difference of its first term is 31
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