2019 AMC 8 Problems/Problem 20
Problem 20
How many different real numbers satisfy the equation
Solution
We have that if and only if . If , then , giving 2 solutions. If , then , giving 2 more solutions. All four of these solutions work, so the answer is . Further, the equation is a quartic in , so by the fundamental theorem of algebra, there can be at most four real solutions.
See Also
2019 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 19 |
Followed by Problem 21 | |
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