Respuesta :
1 sign change when x=1, there is 1 positve root
2 sign changes when x = -1. there are 2 possible negative roots
since complex roots come in 2s, there might be 0 negative roots, and 2 complex roots
close, but we cant say for sure that there are 0 or 2 negative roots; or 0 or 2 complex roots
Positive Real: 1
Negative Real: 0, or 2
Complex: 0, or 2
Answer: Positive roots = 1
Negative real root =0 or 2
complex roots=0 or 2
Step-by-step explanation:
Given cubic polynomial f(x) = [tex]4x^3 + x^2 + 10x - 14[/tex]
By Descartes rules of signs
as this polynomial is already arranged in descending order and has only 1 sign change which means it has 1 positive real root.
Now change signs of coefficients of odd powered terms we get
[tex]-4x^3 + x^2 - 10x - 14[/tex] then we have 2 sign changes which gives 2 or zero negative real roots .
For complex roots , we know that it is a cubic polynomial i.e. it has exactly 3 roots and complex roots always occur in pair, Therefore it will have zero or 2 complex roots.