Decartes Rules

posted by .

Use Decartes Rule of signs to determine the possible number of postive and negative real zeros for the given function. Please check my answers?

1. f(x)=-7x^9+x^5-x^2+6
This is what I did:
There are 2 sign changes

f(-x)=-7(-x)^9+(-x)^5-(-x)^2+6
There are 2 sign changes

So, are there 2 or 0 positive zeros, 2 or 0 negative zeros?

2. f(x)10x^3-8x^2+x+5
There are 2 sign changes

f(-x)=10(-x)^3-8(-x)^2+(-x)+5
There are 2 sign changes

So, are there 2 or 0 positive zeros, no neggative zeros?

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Decartes Rule of Signs

    Could you explain to me decartes Rule of signs?
  2. Decartes Rule of Signs-Check Problems

    Use Decartes Rule of signs to determine the possible number of postive and negative real zeros for the given function. 1. f(x)=-7x^9+x^5-x^2+6 This is what I did: There are 2 sign changes f(-x)=-7(-x)^9+(-x)^5-(-x)^2+6 There are 2 …
  3. Decartes Rule

    Can you please check my work? Use Decartes Rule of signs to determine the possible number of postive and negative real zeros for the given function. 1. f(x)=-7x^9+x^5-x^2+6 This is what I did: There are 2 sign changes f(-x)=-7(-x)^9+(-x)^5-(-x)^2+6
  4. Pre-Calc

    I know about Descartes Rule but I don't really get how to figure this out-Please check my answers- I don't get this one find number of possible positive and negative real roots of f(x) = x^4-x^3+2x^2 + x-5 I think there are 3 sign …
  5. college allgebra

    f(x)=x^6+4x^5+4x^4+3x^3-x^2-5x+4 Find the maximum number of real zeros, and Use Descartes's rule of signs to determine how many positive and how many negative zeros the function has. You do not need to find the zeros.
  6. calculus

    For the following function f(x)=2x^4-6x^2+2x-1. Find the maximum number of real zeros and Use Descartes's rule of signs to determine how many positive and how many negative zeros the function has. You do not need to find the zeros.
  7. college algebra--please help

    what does Descartes rule of signs tell you about the possible number of positive real number zeros and the possible number of negative real zeros of the function?
  8. Math Algebra

    Use Descartes' Rule of Signs to determine the possible number of positive real zeros and the possible number of negative real zeros for the function. 1. 9x^6-5x^4-2x^3+8x^2-4x=0 2. -9x^4+5x^3-2x^2+4x-3=0
  9. Math

    Using the Descartes Rule of Sign count the number of sign changes of f(x) and determine the number of positive real zeros. 1. f(x)=x^3+x^2-10x-24 My answer: because the signs don't change the answer would be: "0 sign changes of f(x), …
  10. Math

    Using the Descartes Rule of Sign count the number of sign changes of f(-x) and determine the number of negative real zeros. 1. f(x)=x^3+x^2-10x-24 My answer: A few signs due change but not enough to say they changed." 0 sign changes …

More Similar Questions