1989 AHSME Problems/Problem 29
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Problem
What is the value of the sum
Solution
By the Binomial Theorem,
.
Using the fact that ,
,
,
, and
, the sum becomes:
.
So, .
Using De Moivre's Theorem, .
And finally, .
See also
1989 AHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 28 |
Followed by Problem 30 | |
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