2019 AMC 12B Problems/Problem 8
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Problem
Let . What is the value of the sum
?
Solution
First, note that . We can see this since
Using this result, we regroup the terms accordingly:
Now it is clear that all the terms will cancel out (the series telescopes), so the answer is
.
See Also
2019 AMC 12B (Problems • Answer Key • Resources) | |
Preceded by Problem 7 |
Followed by Problem 9 |
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All AMC 12 Problems and Solutions |
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