2017 AMC 12A Problems/Problem 17
Problem
There are different complex numbers
such that
. For how many of these is
a real number?
Solution
Note that these such that
are
for integer
. So
This is real iff is even
. Thus, the answer is the number of even
which is
.
See Also
2017 AMC 12A (Problems • Answer Key • Resources) | |
Preceded by Problem 16 |
Followed by Problem 18 |
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All AMC 12 Problems and Solutions |
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