1965 AHSME Problems/Problem 20
Problem
For every the sum of n terms of an arithmetic progression is . The th term is:
Solution
In order to calculate the th term of this arithmetic sequence, we can subtract the sum of the first terms from the sum of the first terms of the sequence. Plugging in and as values of in the given expression and subtracting yields Simplifying gives us the final answer of .
See Also
1965 AHSC (Problems • Answer Key • Resources) | ||
Preceded by Problem 19 |
Followed by Problem 21 | |
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