1989 AHSME Problems/Problem 29
Problem
What is the value of the sum
(A) (B) (C) 0 (D) (E)
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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