Example: Complex roots for a quadratic | Algebra II | Khan Academy

[@trooperboot4056]

Shoutout to all the people grinding out there🏆

[@Andre-bi3gq]

haha 🙏🙏

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🙌🏻🙌🏻

[@bradwillard8009]

i have a final tomorrow and have no idea what is going on

[@TheRealFredbearPlush]

real.

[@evaniceface]

How did it go

[@bradwillard8009]

@@evaniceface it’s been 4 years but i definitely passed so we’re good

[@evaniceface]

@@bradwillard8009nice 👍👍

[@haydenporter8629]

@@bradwillard8009bruh i got a final today as well

[@ChriSportGuy]

A random non-real root disliked this video

[@operationghostgaming4698]

thanx my teacher went over this once and it was only a matter of 2 and a half hours. I guess thats how algerbra honors works.

[@thejonathan130]

1759 views, only one person asks a question and only 1 other person thaks khan for his work.... what is this world coming to? THANK YOU SALMAN KHAN YOU ARE A HERO IN THE WORLD OF MATHIMATICS!!!!

[@aaronrodriguez1410]

thejonathan130 its just a question goodness

[@seifomran]

Thanks man 😊😊 from Egypt 🇪🇬

[@MikeMike-yc8gg]

2:49 Square root of - 4 3:21 4:46

[@faniSuarez]

How to convert it back to a quadratic?

[@jboy219]

Thank you, Khan Academy.

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[@helihelixggs]

Thank you

[@김은진-h8g]

good

[@sleepysoul-zzz]

Thank you so much, Khan Academy. You have helped more people than you will ever know.

[@Om0plata1]

How do I get the equation if im initially given the complex roots ?

[@Dyenosoreusrex]

i, i captain....

[@skullkazor2]

Thanks so much! I wasn't sure at first if I was able to involve the imaginary number i if the equation didn't already have it included somewhere. This helped me more than I could have possibly hoped for!

[@ryankile5323]

9:15 didn't dividing everything by 2 get rid of the 2 already, why did 4 become 2 then get divided by 2 a 2nd time?

[@thejonathan130]

Im just wondering this because this is what I was just taught in school for the past week, but isnt it easyer instead of (+or-) just to have your new numbers looking like this (I will use 10 and 5 as examples) y=(x2+10x+25)-25+5 the 25 are the half b squred value inside and out of the brakets...

[@keytoproductivity_1915]

thanks this really helped

[@kuldeepsen3364]

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[@keytoproductivity_1915]

@@kuldeepsen3364 umm no

[@animationspace8550]

@@keytoproductivity_1915 lol

[@evaniceface]

Guys am I stupid or is this hard

[@Rxn-pj5up]

Yes.

[@RupanshuKumarSingh]

You're stupid

[@rayv1918]

This is hard.

[@opsalbit]

Is hard if you define hard as something that requiere practice and knowledge of previus content in order to undertand the concepts

[@CriminallyUnderatted]

@@rayv1918 L O L

[@لجينمحمد-ط1م]

My great teacher❤

[@thejonathan130]

here is my version (S= squared) y=2xS-6x+5 > y=(2xS-6x)+5 > y=2(x-3)S+5 > b=-3 half b=-1.5 half b,S=2.25> y=2(x-3+2.25)S-2.25+5 > y=2(x-1.5)+2.75 and than thats the farthest you go.... and then to get the vertex you take V=1.5 , 2.75... please correct me if im wrong.. BUT NOT ON MY SPELLING...

[@woohwison3296]

THANK YOU!!!

[@takayoutube98]

It took me 30mins to figure out why (-1)^2 = -1 . since i^2=-1, (-i)^2 =-i x -i= i^2 ---------->-1

[@Alexandru_007x]

Thanks man

[@masterwulfgar1657]

8:41 -i^2 is equal to 1 not -1

[@shuvrojyotighosh6063]

yes he was wrong -i^2 = i

[@hellgod1809]

i dont understand why they cant teach us basic complex nos and put this concept in 10th class itself instead of putting the whole thing in 11th

[@manarabbas9240]

They put the whole complex numbers and its concepts in 12th class for us💀 we’re completely lost istg

[@monkeyglocks]

at 8:06 can someone explain to me where this 6 is coming from because I can't figure it out.

[@theophonchana5025]

Discriminant = -4

[@yesidohaveaverysmallpenisb5458]

Okay but how do I graph it

[@HUSSEIN.HUALBA]

thank you👏👏😍 from Baghdad 😤

[@MathCuriousity]

Why do we sometimes get extraneous solutions when using quadratic formula?

[@prettyhailey6]

Thank you so much

[@qud_ratol]

What is the difference between real and nor real roots?

[@axalate4572]

Real roots are the roots that really exist for a quadratic equation but unreal/imaginary roots are something which dont exist cuz they doesn't satisfy the rules of the real numbers.Unreal roots are getting when the discriminant is negative inside the square root the final answer is not considered a real number because inside a square root the number must be positive

[@Continuious]

شكرا

[@theophonchana5025]

Square root of -4 = error

[@theophonchana5025]

sqrt (-4) = error

[@idkwhy77]

Ty

[@mysticorange4796]

Formula inventors name is sridhara acharya who is an indian

[@theophonchana5025]

a = 2 b = -6 c = 5

[@priyankapri4542]

Thank you sir

[@Tommy_keyys]

What’s going on?

[@Rxn-pj5up]

ur dads wedding

[@Rxn-pj5up]

(maaf karna) (marjao)

[@rayv1918]

I, myself dont know.

[@element1192]

so, if (-b±sqrt(d))/2a = x, then (-b±sqrt(-d))/2a = xi

[@SmithGarridoLe96]

DAFUQ where did he get that -i^2= -1

[@theartemys]

square root of -1 is equal to +i and -i

[@paritoshagarwal8840]

i=root -1 i^2=root -1 * root -1= -1

[@That_One_Guy...]

if you square a negative number (no matter if it's imaginary number or real number) you will also get the same result with it's positive counterpart squared so i^2 = -1 and so does (-i)^2 = -1

[@bugunia3558]

if i squared = -1, i didn't understand why -i squared also equals to -1

[@dirtysquirrel8611]

-i times -i equals positive i^2, and i^2 is -1. It tripped me up too for a bit

[@theophonchana5025]

sqrt (-4) = invalid input

[@itsnethergamingboyz3335]

i understand everything till 3-i/2 but after that i don't understand what you are telling

[@DinoNuggets371]

POV: your in algebra 2

[@licecollector6199]

That’s it. I’m failing.

[@kuldeepsen3364]

Hi, contact me on my WhatsApp [phone] for any kind of help like questions solutions etc in any of the subjects. Try this, it's really helpful.

[@chrispastore1548]

Not sure about -i^2=-1.. i^2=-1 so wouldnt that make it (-1)*(-1)?!?! wolfram alpha is telling me it is a positive 1

[@Nobody-Nowhere-Nothing]

-i does not equal -1, -i is - √-1, so when you multiply -i times -i you would have to start with the i's first. i^2 is -1 then you multiply it by the -(1) signs. -(1) x -1 is 1 then -(1) x 1 is -1. So -i^2 is -1

[@elijahmelton922]

GreenDemon125 beat me to it

[@JohnSmithTheExplorer]

5 dislikes? Dafuq?

[@zepliveson]

derp :/

[@devanwebb496]

8 years ago.. dang

[@animationspace8550]

I feel your pain brother

[@_IvanMichael]

derpy derp

[@nocturnalvisionmusic]

@@_IvanMichael I love it ^_^

[@stxlla_j10]

This is further maths work, otherwise you would write that x has no solutions

[@GMAH111]

You're right, that's why it says complex roots.

[@dawnplaya5596]

Blessed Soul uhh, it's a high school requirement to take Algebra 2

[@Jorge-cs5zg]

Im so... Screwed...

[@tobiadedoyin811]

I don't understand how -i^2 = -1?!

[@kuldeepsen3364]

Hi, contact me on my WhatsApp [phone] for any kind of help like questions solutions etc in any of the subjects. Try this, it's really helpful.

[@Continuious]

The comment are too old

[@ferrerorochers5129]

what

[@ViewersOP295]

This quadratic fromula discovered by lndian Mathametisian name " Sridhar acharcha".

[@لجينمحمد-ط1م]

My great teacher❤

[@jorgearchitecture8643]

Thank you sir