Difference between revisions of "2021 JMPSC Accuracy Problems/Problem 4"
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+ | The only numbers that are their own reciprocals are <math>1</math> and <math>-1</math>. Thus, |
Revision as of 12:37, 11 July 2021
Problem
If is its own reciprocal, find the product of all possible values of
Solution
From the problem, we know that
Thus, or . Our answer is
~Bradygho
Solution 2
We have , so . By Vieta's our roots and amount to
~Geometry285
Solution 3
Therefore, the product of the root is
~kante314
Solution 4
The only numbers that are their own reciprocals are and . Thus,