1991 AHSME Problems/Problem 25
Problem
If and for then is closest to which of the following numbers?
Solution
It is well known that , so we can put this in and simplify to get that the general term of the product is Now by writing out the terms, we see that almost everything cancels (telescopes), giving which is almost , so closest to
See also
1991 AHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 24 |
Followed by Problem 26 | |
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