Complex Numbers : Roots of a cubic equation : ExamSolutions

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  • Опубліковано 12 лют 2012
  • Complex numbers: finding the roots of a cubic equation.
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КОМЕНТАРІ • 53

  • @bienaime8344
    @bienaime8344 9 місяців тому +1

    11 years on and this video is a blessing- Thank you!

  • @ay7565
    @ay7565 3 роки тому +1

    Exactly what I needed! Thank you so much for the perfect explanation

  • @mavulandlela
    @mavulandlela 7 років тому +3

    Thank you, that has greatly helped my understanding

  • @neilborg2756
    @neilborg2756 2 роки тому

    thank you so much for the upload sir! i wasn't aware of such a straightforward method!

  • @ChiragDhussa
    @ChiragDhussa 8 років тому +3

    Thank u so mch sir..this was exactly what I was looking for..

  • @rounaksinghbuttar9083
    @rounaksinghbuttar9083 4 роки тому +1

    Very nicely taught, thank you very much Sir!

  • @chris-sophievandervlugt2928
    @chris-sophievandervlugt2928 8 років тому +1

    if only my maths teacher had described it like this.so much easier to understand now thank you.

  • @practicepractice512
    @practicepractice512 3 роки тому

    Thank you so much!

  • @parshu7926
    @parshu7926 8 років тому +4

    wow superb!!its applicable to all numerical. i have been searching since many days and i got it finally..thanks lot u sir.

  • @deepjyotidas5762
    @deepjyotidas5762 7 років тому

    That was very help sir. Thank you.

  • @laurencrom
    @laurencrom 12 років тому

    This is a great video. Keep it up!

  • @thilakkumara8975
    @thilakkumara8975 9 років тому +3

    Thank You So Much :) This really helped me a very lot ! Thanks Again !

  • @Latestsightings
    @Latestsightings 10 років тому +1

    Thanks soooo much!

    • @ExamSolutions_Maths
      @ExamSolutions_Maths  10 років тому +1

      You're welcome. Thanks for using my site.

    • @jayagnihotri5807
      @jayagnihotri5807 9 років тому

      ExamSolutions
      Another fantastic video sir.
      Can I just ask you is the only way to get the quadratic factor by long division, I used the method but was wondering is there an alternative method.
      And also how would you obtain the roots of an equation such as x^4-3x^3+2x^2-3x+2?
      Regards sir :)

    • @aashsyed1277
      @aashsyed1277 3 роки тому

      @@ExamSolutions_Maths YOU ARE THE BEST!!

    • @vanbrecken8147
      @vanbrecken8147 3 роки тому

      a trick : you can watch movies on Flixzone. Been using them for watching a lot of movies these days.

    • @raphaelsimon1847
      @raphaelsimon1847 3 роки тому

      @Van Brecken yea, I have been watching on Flixzone for months myself :D

  • @jennyzhang2810
    @jennyzhang2810 3 роки тому +2

    Hi sir, this has been very helpful. Do you mind doing more IB videos? It will be truly appreciated!

  • @oscarfeingold8630
    @oscarfeingold8630 2 роки тому

    best video on this topic really useful

  • @ExamSolutions_Maths
    @ExamSolutions_Maths  12 років тому

    For the roots to be a complex conjugate pair the equation must consist of terms of the form az^3+bZ^2+cZ+d=0 where a does not equal zero and a, b, c, d and are real. d for this equation is imaginary and so this rule does not hold. Your roots are correct though.

  • @Hipster523
    @Hipster523 8 років тому

    Thx was very helpful

  • @hangkertzy9722
    @hangkertzy9722 3 роки тому +1

    thankyou so much!!

  • @mrfreerunners1
    @mrfreerunners1 Рік тому +1

    at 4:20 you say f(1)=22 but I got 24 on my calculator. And it is the same for -1

  • @mdjahin99
    @mdjahin99 6 років тому

    Thank yo Sir!

  • @hninsumonwin4189
    @hninsumonwin4189 8 років тому +2

    when you write down the quadratic formula, I didn't see there is no minus in front of b.
    Is the formula like that? (-b±square root of b^2-4ac)/2a?

    • @TWENTYSEVENSTORIES
      @TWENTYSEVENSTORIES 4 роки тому +1

      b is minus 6, so the negative that is always in the formula cancels this negative out to give positive 6. Hence why there is no negative sign when substituted in to the formula.

  • @mehdi9353
    @mehdi9353 9 років тому +1

    For f(1), the answer is 24 not 22. However, great video!! Thanks!

  • @tenki330
    @tenki330 7 років тому

    thx!

  • @johnkombapangai-yd3lu
    @johnkombapangai-yd3lu Рік тому

    Very good

  • @holyshit922
    @holyshit922 12 років тому

    Use one of following substitutions to get quadratic equation
    Z=U+V
    Z=U+\frac{7}{3U}
    You can also get formula for trigonometric function of triple angle
    with substitution like this
    Z=2\sqrt{-\frac{7}{3}}\cos{\theta}

  • @aihamal-shummari721
    @aihamal-shummari721 6 років тому +1

    Thank you so much, god bless you good sir.

  • @phm04
    @phm04 2 роки тому +1

    is there a way to this without trial and error

  • @mohammadalam3021
    @mohammadalam3021 6 років тому

    What should I do with the remainder if I get it in a question?

  • @abhilashajb4ever
    @abhilashajb4ever 9 років тому

    what if we need to find roots in terms of w ?

  • @jamaicaboy544
    @jamaicaboy544 7 років тому +2

    What if none of the factors equate the equation to 0

  • @zoerose1892
    @zoerose1892 4 роки тому

    You're an absolute life saver, thankyou so much for these videos!

  • @thecheetahisfasterdandelion
    @thecheetahisfasterdandelion Рік тому +1

    exams in 13hrs and i comepletely forgot about this topic thank you

  • @joelalexandre9865
    @joelalexandre9865 10 років тому

    And in this case: x^4+2x^3-x^2+2x+1, how to know its roots?

  • @simategeoffrey.s8923
    @simategeoffrey.s8923 7 років тому

    indeed,......

  • @prashantsharma7788
    @prashantsharma7788 3 роки тому +1

    ❤️❤️❤️🙏🙏

  • @holyshit922
    @holyshit922 12 років тому

    There should be
    Z=U-\frac{7}{3U} instead of
    Z=U+\frac{7}{3U}

  • @Scratchfan321
    @Scratchfan321 2 роки тому

    It appears as though I must guess

    • @Scratchfan321
      @Scratchfan321 2 роки тому

      After plugging in numbers (Guessing) it worked.

  • @benjaminnetanyahu9952
    @benjaminnetanyahu9952 Рік тому

    I think I just found the Gordon Ramsay of math

  • @bostangpalaguna228
    @bostangpalaguna228 4 роки тому

    *Quick Fact*
    If a cubic polynomial given has 2 real roots, those two must be identical.