Problem:
Prove that there do not exist pairwise distinct complex numbers , , , and such that
Problem:
Prove that there do not exist pairwise distinct complex numbers , , , and such that
Solution:
First suppose none of them are . Let the common value of the four expressions be , and let . Then for ,
However, Vieta's tells us , meaning , so , a contradiction.
Now if , then . Then without loss of generality , , and . But then , a contradiction.
Thus, there do not exist distinct complex numbers satisfying the equation.
Solution:
Subtracting the first two equations and dividing by gives . Similarly, . So, . Similarly, . So, . Similarly, . Now by Pigeonhole, two of these 4 must be the same.