Question

Using complete sentences, describe how you would analyze the zeros of the polynomial function f(x) = -3x5 - 8x4 +25x3 - 8x2 +x - 19 using Descartes' Rule of Signs.

Answer 1

There are 4 positive real roots because there are four sign changes. To find the negative put -x in for x..... \[f(-x) = -3(-x)^5 - 8(-x)^4 +25(-x)^3 - 8(-x)^2 +(-x) - 19\] to get ....\[3z^5-8z^4-25z^3-8z^2-z-19\] so there is 1 negative real root. Then I make this chart to find the complex...