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evy15

Find all zeros 5x^5-20x^4-40x^3-16x^2-45x+180=0

  • one year ago
  • one year ago

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  1. evy15
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    @zepp

    • one year ago
  2. Asad0000
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    What do you mean by "Find all zeros" ?

    • one year ago
  3. evy15
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    find the zeros of th eq

    • one year ago
  4. wio
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    Use rational root theorem to find first zero. Then use synthetic division to factor it out.

    • one year ago
  5. mark_o.
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    hi @evy15 are you in numerical analysis? the root are -2.07316, 1.2355, 5.5573 and two complex roots check it for yourself if they are true

    • one year ago
  6. matricked
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    @evy though the equation is 5x^5-20x^4-40x^3-16x^2-45x+180=0 correct bu t may be i feel u have typed in -16X^2 instead of 160x^2

    • one year ago
  7. evy15
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    no its correct

    • one year ago
  8. evy15
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    can someone please help me and explain to me how to begin this problem

    • one year ago
  9. evy15
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    can someone respond

    • one year ago
  10. mathmate
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    Have you done numerical methods in your course? This is not a problem that can be solved by factorization, or rearrangements. I suggest you triple check the question.

    • one year ago
  11. evy15
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    its correct can you tell me how to begin

    • one year ago
  12. mathmate
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    It can be solved numerically, or graphically. Are these expected methods to use in your course?

    • one year ago
  13. evy15
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    yes the thing is i missed a day in class and now i dont know how to work this out

    • one year ago
  14. mathmate
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    Are you working on factorization, Descartes rule of signs, etc.? I suggest you check your course outline to see what you're expected to know, or check with a friend to see what has been done that day. The prof would also be pleased to tell you what has been covered that day. This problem requires numerical methods which are techniques completely different from your previous problems.

    • one year ago
  15. evy15
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    can u help me and explain it to me

    • one year ago
  16. evy15
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    i have tried to use the book but i keep getting it wrong

    • one year ago
  17. mathmate
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    What is the name of your math course?

    • one year ago
  18. evy15
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    Algebra 2

    • one year ago
  19. mathmate
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    Then there is probably another typo in the question.

    • one year ago
  20. evy15
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    there isn't, i already checked

    • one year ago
  21. mathmate
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    I believe you, but your prof made a typo! Check in the index of your textbook to see if Newton's method is in there. What is the title of your textbook?

    • one year ago
  22. evy15
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    ok

    • one year ago
  23. evy15
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    Im not sure, hold on

    • one year ago
  24. evy15
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    Holt McDougal Larson Algebra 2

    • one year ago
  25. mathmate
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    Can you find "Newton's method" in the index?

    • one year ago
  26. mathmate
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    On which chapter are you working?

    • one year ago
  27. mathmate
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    Is it paper home-work or online?

    • one year ago
  28. evy15
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    its a take home test and i couldnt find it

    • one year ago
  29. mathmate
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    As matricked pointed out, IF -16x^2 had been +160x^2, then there are rational roots obtainable by grouping. 5x^5-20x^4-40x^3+160x^2-45x+180 =5(x^5-4x^4-8x^3+32x^2-9x+36) \(= 5( x^4(x-4) -8x^2(x-4) -9(x-4)) \) \(= 5(x-4)(x^4-8x^2-9) \) \(= 5(x-4)(x^2-9)(x^2+1) \) \(= 5(x-4)(x+3)(x-3)(x^+1) \)

    • one year ago
  30. mathmate
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    *last factor is \( (x^2+1) \)

    • one year ago
  31. evy15
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    ok do you solve for them now

    • one year ago
  32. evy15
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    hold on a second, im sorry

    • one year ago
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