Ask questions and get helpful responses.

Algebra

f(x)=2x^4+5x^2-6x+9
Use Descartes' Rule of Signs to determine the possible numbers of positive and negative real zeros.

  1. 👍
  2. 👎
  3. 👁
  4. ℹ️
  5. 🚩
  1. positive: two sign changes, max two real roots.
    negative: zero sign changes, zero real roots

    min number of non-real roots:
    4-(2-0)=2

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩
    👤
    bobpursley
  2. one flip in f(x) from 5 x^2 to - 6 x
    second from -6 x to +9

    no flips in f(-x) = 2x^4 + 5x^2 + 6x + 9

    so two or zero positive real roots

    check with
    http://www.emathhelp.net/calculators/algebra-1/descartes-rule-of-signs-calculator/

    1. 👍
    2. 👎
    3. ℹ️
    4. 🚩

Respond to this Question

First Name

Your Response

Still need help? You can ask a new question.