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evy15

  • 2 years ago

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

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  1. evy15
    • 2 years ago
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    @zepp

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

  3. evy15
    • 2 years ago
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    find the zeros of th eq

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

  5. mark_o.
    • 2 years ago
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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

  6. matricked
    • 2 years ago
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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

  7. evy15
    • 2 years ago
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    no its correct

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

  9. evy15
    • 2 years ago
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    can someone respond

  10. mathmate
    • 2 years ago
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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.

  11. evy15
    • 2 years ago
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    its correct can you tell me how to begin

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

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

  14. mathmate
    • 2 years ago
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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.

  15. evy15
    • 2 years ago
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    can u help me and explain it to me

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

  17. mathmate
    • 2 years ago
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    What is the name of your math course?

  18. evy15
    • 2 years ago
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    Algebra 2

  19. mathmate
    • 2 years ago
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    Then there is probably another typo in the question.

  20. evy15
    • 2 years ago
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    there isn't, i already checked

  21. mathmate
    • 2 years ago
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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?

  22. evy15
    • 2 years ago
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    ok

  23. evy15
    • 2 years ago
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    Im not sure, hold on

  24. evy15
    • 2 years ago
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    Holt McDougal Larson Algebra 2

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

  26. mathmate
    • 2 years ago
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    On which chapter are you working?

  27. mathmate
    • 2 years ago
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    Is it paper home-work or online?

  28. evy15
    • 2 years ago
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    its a take home test and i couldnt find it

  29. mathmate
    • 2 years ago
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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) \(= 5( x^4(x-4) -8x^2(x-4) -9(x-4)) \) \(= 5(x-4)(x^4-8x^2-9) \) \(= 5(x-4)(x^2-9)(x^2+1) \) \(= 5(x-4)(x+3)(x-3)(x^+1) \)

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

  31. evy15
    • 2 years ago
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    ok do you solve for them now

  32. evy15
    • 2 years ago
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    hold on a second, im sorry

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