Complex numbers: Solving Equations (with example)

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  • Опубліковано 4 жов 2024
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    #StartLearningMathematics
    This video is about solving simple equations with complex numbers, also known as extracting roots from complex numbers. There is a simple algorithm and a nice visualisation for this.
    I hope that this helps students, pupils and others.
    (This explanation fits to lectures for students in their first year of study: Mathematics for physicists, Mathematics for the natural science, Mathematics for engineers and so on)

КОМЕНТАРІ • 78

  • @leNnard_
    @leNnard_ 4 роки тому +24

    My mind is blown, you took all my confusion and replaced it with knowledge...danke für das schöne video!

  • @ΘΑΝΟΣΠ-ψ1θ
    @ΘΑΝΟΣΠ-ψ1θ 3 роки тому +13

    No one has ever taught me this way. Thank you, you are amazing!!

  • @essayprometheus
    @essayprometheus 4 роки тому +18

    You are a freaking genius, i have never thought about solving complex numbers in this way. It feels like everything just makes SENSE. Thank you so much

    • @estebansanchezsevilla1930
      @estebansanchezsevilla1930 Рік тому +3

      Man its de Moivre's theorem, did u pay attention in class?

    • @multimeme5935
      @multimeme5935 3 місяці тому +1

      @@estebansanchezsevilla1930 I did pay attention, but unfortunately our teacher just write the formula and solve some problems even without any graph.

  • @tortugatech
    @tortugatech 4 роки тому +5

    Great explanation! Rememebered all about complex equations i forgot since freshman year

  • @ishmealm001
    @ishmealm001 3 роки тому +13

    Amazing explanation, I've never understood this so well ! Thank you very much !!

  • @sohaib_mer-
    @sohaib_mer- 3 місяці тому +1

    god i knew going through the exponential form was the most straightforward but NO, i set
    2+2i = (a+bi)^3 and god that route was so longgggg
    great video keep up!

  • @theblackswordsman8400
    @theblackswordsman8400 4 місяці тому +2

    This video explained waaaay better than any of my professors could have! Thank you so much!
    i just have a quick question regarding this explanation. At 11:25 i do not understand why you multiplied everything by 1/3 again. Could you please explain as to why you did this? thanks

  • @arbenkellici3808
    @arbenkellici3808 Рік тому +1

    Great explanation! Easy and clear for me, even though i am not a mathematicien Keep it up professor!

  • @HDitzzDH
    @HDitzzDH 3 роки тому +3

    It probably would've been better to explain the "1/3" part in the argument from the fact that:
    z = re^(iθ), thus z^3 = r^3*e^(3θ), thus 3θ = π/4 + 2π*k which means that:
    θ = π/12 + 2π/3*k

  • @tasosrokos498
    @tasosrokos498 2 роки тому +1

    Du bist der Wahnsinn...! Danke für alles!

  • @sgottk2928
    @sgottk2928 2 роки тому +3

    Awsome video, just one question
    In the step where you have
    z³ = √(8) * e^(i(π/4 + 2πk))
    And then you take all to the 1/3 power to get
    z = √(8)^(1/3) * e^(i(π/4 + 2πk)*1/3)
    Over the reals, we have that for example, √x² = |x| that we can use to solve things like
    x²=4
    |x| = √4
    x = +-√4
    But is there a thing that grants that √Z² = Z(k) (meaning, the results of z in function of k) over the complex plane?

  • @bridgeunwort61
    @bridgeunwort61 3 роки тому +6

    You said that the number of solutions we'll get is equal to the exponent. What if the exponent isn't a whole number, like a fraction, irrational number, or even imaginary/complex?

    • @brightsideofmaths
      @brightsideofmaths  3 роки тому +3

      I only cover natural numbers as exponents here. Otherwise, everything gets much more complicated and this deserves a lot of videos then.

  • @giorgiozannini5626
    @giorgiozannini5626 4 роки тому +2

    Such a beautiful explanation... I love this channel

  • @sinabeyraghdar6292
    @sinabeyraghdar6292 3 роки тому

    Thank you! Explained better than my professor

  • @nanditadey3707
    @nanditadey3707 3 роки тому +2

    Thanks it helped for my exam

  • @heinminoo1618
    @heinminoo1618 4 місяці тому +1

    Thanks

  • @fjorland_norsk3996
    @fjorland_norsk3996 3 роки тому

    dont know why but your voice makes my mind calm and relaxed. Also great video

  • @theo9362
    @theo9362 2 роки тому +1

    This was helpfull! Thanks

  • @hasnainalfarabi6420
    @hasnainalfarabi6420 11 місяців тому

    Thank You So Much Sir

  • @tathagatasenchowdhury3278
    @tathagatasenchowdhury3278 3 роки тому +2

    Nice video Fabulous!

  • @GeorgZiom
    @GeorgZiom 3 роки тому +1

    Love this video, man

  • @aminareddead
    @aminareddead 5 місяців тому

    Thanks a lot ❤

  • @sangachidam3219
    @sangachidam3219 2 роки тому

    Excellent thanks very much

  • @TheMounten1
    @TheMounten1 2 роки тому

    THANKYOU SO MUCH!!!!!!!!!

  • @pawekruczkowski7940
    @pawekruczkowski7940 3 роки тому

    Amazing video! Thank you

  • @georgemaxwell6235
    @georgemaxwell6235 11 місяців тому

    tysm very helpful

  • @gatlatwal8499
    @gatlatwal8499 2 роки тому

    Please help me calculate this
    Given that (√3-i) is a square root of the equation Z^9+16(1+i)z^3+a+ib=0
    What is the value of a and b?

  • @nour_780
    @nour_780 Рік тому

    You are amazing, Thanks

  • @gerben880
    @gerben880 4 роки тому +1

    nice ty

  • @aidanbryant154
    @aidanbryant154 4 роки тому +2

    Better than how Sal Kahn explained it, nice vid

  • @offthepathworks9171
    @offthepathworks9171 9 місяців тому

    So you wouldn't say this is precalculus? Great video as always!

    • @brightsideofmaths
      @brightsideofmaths  9 місяців тому +1

      I mean it's an important calculation tool but also not so simple.

    • @offthepathworks9171
      @offthepathworks9171 9 місяців тому

      @@brightsideofmaths much appreciated.

  • @AboudHabibi-v5k
    @AboudHabibi-v5k 3 роки тому +1

    When x is equal to 0 how would you find the argument? For example this complex equation: 0 - 7776i

    • @brightsideofmaths
      @brightsideofmaths  3 роки тому

      Sketch the number in the complex plane and try to guess the correct angle :)

    • @solomonkimba
      @solomonkimba Рік тому

      @@brightsideofmaths can we say 3pi/2 radian

  • @nanditadey3707
    @nanditadey3707 3 роки тому +3

    I would like to support this channel

    • @brightsideofmaths
      @brightsideofmaths  3 роки тому +2

      You can visit the Steady-page :) steadyhq.com/en/brightsideofmaths

    • @nanditadey3707
      @nanditadey3707 3 роки тому

      @@brightsideofmaths Thankyou for reminding me

    • @nanditadey3707
      @nanditadey3707 3 роки тому

      Can you please taught me how to do the sums of the topic: "Idea of Speed, Distance and time" ?

  • @ShaolinMonkster
    @ShaolinMonkster 3 роки тому

    very good

  • @letsgo6374
    @letsgo6374 4 роки тому +1

    How to convert it to a+bi form?
    So i can plot itu

    • @ΘΑΝΟΣΠ-ψ1θ
      @ΘΑΝΟΣΠ-ψ1θ 3 роки тому +1

      z=re^iφ
      and
      e^iφ=cosφ + isinφ (Euler)
      so
      z = r(cosφ + isinφ)
      and by doing the calculations for each root (solution) , you get each of them in a+bi form

  • @duckymomo7935
    @duckymomo7935 4 роки тому +1

    Complex analysis??

  • @jimtownsend6139
    @jimtownsend6139 3 роки тому +2

    Great video, but you threw me a bit at the beginning with the pi/4 = 45 degrees.. It's kind of a sudden leap from radians to degrees..
    In relation to a unit circle, Pi/4 = .7854... radians. There are 57.3 degrees in a radian, so .7854 radians X 57.3 degrees = 45 degrees.

    • @brightsideofmaths
      @brightsideofmaths  3 роки тому +4

      360° - One circle: 2 Pi
      180° - Half a circle: 1 Pi
      90° - Quarter circle: 1/2 Pi
      45° - Eighth of a circle: 1/4 Pi
      You do not need a calculator for that :)

    • @jimtownsend6139
      @jimtownsend6139 3 роки тому

      Quick reply.. Thanks.. I took this over 40 years ago and with these COVID lock downs, decided to use the down time to refresh my memory :) I know the relationships, but I was thinking of someone who didn't. They would pull out a calculator type in pi/4 and get .7854... Just a small thing.. Still a great video.

    • @brightsideofmaths
      @brightsideofmaths  3 роки тому +1

      @@jimtownsend6139 Yeah, of course, it is allowed to just use a calculator but I want to activate some thinking processes with my videos. I'm glad you liked the video :)

  • @keytoproductivity_1915
    @keytoproductivity_1915 4 роки тому +2

    do u speak german?
    sprichst du deutsch?

    • @brightsideofmaths
      @brightsideofmaths  4 роки тому

      Yeah, here is the German version of this video: ua-cam.com/video/T2D9y_77su0/v-deo.html

    • @pervezhassan3184
      @pervezhassan3184 3 роки тому

      I love Germany 🥰😍also the people of Germany 😍I'm a student of mathamatics. I think also you like mathematics so if you friendly you can speak with me to discuss mathematical problem as Friend. I'm not a youtuber just visitor also learning math. So i need honest and good person to combinedly learn mathematics. As ur wish dear. Tnx. 🙂

  • @laurinwezel6577
    @laurinwezel6577 Рік тому

    there any one else who thinks his accent, especially for words like "rewrite", is really cute?

  • @imwickedd5109
    @imwickedd5109 3 роки тому

    🔥🔥🔥

  • @conradasante2817
    @conradasante2817 3 роки тому

    The actal de moivrrrer say r power n but u made it power 1 over n
    Please check that

    • @brightsideofmaths
      @brightsideofmaths  3 роки тому

      What do you mean? We want to calculate roots, so power 1/n :)

  • @NiragireJeanclaude-fm9vl
    @NiragireJeanclaude-fm9vl День тому

    Thx you support me

  • @tobiaschapinda6771
    @tobiaschapinda6771 3 роки тому

    Solve the equation w^2=1+i............help

  • @l3nn13
    @l3nn13 2 роки тому

    brett

  • @kassawbaye2752
    @kassawbaye2752 3 роки тому

    Equality of complex numbers

  • @nunomiguel555
    @nunomiguel555 3 роки тому

    Me, a pure 10 grade boi
    Uhh??

  • @tj_1260
    @tj_1260 Рік тому

    ok br