Focus and directrix introduction | Conic sections | Algebra II | Khan Academy

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Algebra II on Khan Academy: Your studies in algebra 1 have built a solid foundation from which you can explore linear equations, inequalities, and functions. In algebra 2 we build upon that foundation and not only extend our knowledge of algebra 1, but slowly become capable of tackling the BIG questions of the universe. We'll again touch on systems of equations, inequalities, and functions...but we'll also address exponential and logarithmic functions, logarithms, imaginary and complex numbers, conic sections, and matrices. Don't let these big words intimidate you. We're on this journey with you!

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[cariboux]

Everything is so crystal clear with Khan. Thanks!

[JGott]

I learn something useful every time I watch these - and I'm reminded how mediocre public school classes were for me.
"Why didn't anyone teach me this in school?" My math classes were being given information to accept and regurgitate rather than understand the how or why. But at the end of the day I can't complain too much - we are responsible for ourselves.

[madeofstarlight]

The most useful 4 mins of my life. Oh my god, thank you, Khan academy 😭😭♥️🙏

[AWildOnesie]

THANK YOU!!! This is so incredibly clear and straight to the point!

[Basic-Tron]

You're the best! Best teacher ever!

[yourroyalhighness]

As always, this is amazing. Very helpful

[LiquTelil]

Sir, I have a question what is the fundamental focus and directrix or parabola? And thanks for the video !!!

[harshdhiman]

I already learnt these concepts in my grade11 in Hindustan

[rushabhwaghela]

its outstanding i am clear about parabola tysm sir

[victormaxwellpeters]

But from were did the concept of focus and diretrix came about & How did the know that distance from focus to any point in parabolla is equal to perpendicular distance from that point to diretrix.
why every video I see is silent on that part

[Rs..]

Is directrix just a arbitrary line ? Or where is it drawn?

[penelopeisgoingofftopic]

I'm not the only one who's been re-teaching themself math from scratch with surprisingly much more success in shockingly much less time right? right?

[sccm]

I can't wait to start using these concepts in calculus next semester

[behave]

Great sir
Your videos all are unique and marvellous!

[HabibUrRahman-srwn]

What is the condition for the directrix how far it must be from a parabola for the distance on P will be equal to distance to the directrix

[narindersingh]

Parabola couldn't be made easier than this.:)

[MegaCadette]

Shut up and take all my school fees already. k? thx!

[prabhatsharma]

Hi brother pls cn u tell me which apps u can use in this video

[etorandyll]

The Sliders looked so easy to use. I can't even figure these out. I'm randomly sliding these across to figure it out.
can't we do something Simpler?! this takes 15 minutes per problem!

[bigfrijoles]

no matter what vid i watch i dont think ill ever understand this lmfao