Introduction to complex numbers | Imaginary and complex numbers | 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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[TheColonialTeaCup]

This is great, I just started this course for college this semester and they did not explain anything and just went right in. Khan Academy is a blessing

[ofUnimatrix]

The really awe-inspring thing?  These numbers are needed for all of electronics.  These numbers, which have no correlation whatsoever to anything real, a completely imaginary construct, are required for all of the equations which make our electronics function.

[phicoding]

Thank you so much fifth grade is brutal at my school

[allieroid]

My exam is coming and this really helped me a lot.

[HellaPerformance]

Thank you sal!

Will you please cover indefinite real integrals using couchy's residue theorem next?

[tobiadedoyin]

I am happy I learnt we can not factorize *4-2i*. great lesson!

[bidhutkarki]

I think you are making hd videos of old lessons, it is nice but really want to new lesson from sal except maths and history
Love your work Sal

[iateyourdog]

Ty khan, you are the best teacher ive ever had

[RasaCartaMagna]

I feel like this would be so much easier to understand alongside real-world application examples

[aininsofiya]

why is i² = -1 in the first place? i'm confused.

[armstrongtixid]

So basically all numbers are technically complex numbers?

[tahami]

Yo ain't I to the power 3 suppose to be 1 Im a little confused because that's what our Professor taught he was a lil Drunk but still