1

How to find the exact numbers of positive and negative roots of the polynomial $x^4-12x^2+4$ by using Descartes rule of sign. I can find the maximum number of positive and negative roots using the rule. But how to find the exact numbers?

Jave
  • 1,160
  • 1
    In this case, Descartes rule is not sufficient. But substituting $\ x^2=t\ $ allows to find all the roots of this polynomial. – Peter Sep 02 '19 at 18:16

0 Answers0