Imaginary roots of negative numbers | Imaginary and complex numbers | Precalculus | Khan Academy

Imaginary Roots of Negative Numbers

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[imperialgaming]

Thank you it makes a little more sense now, but i wish you did odd numbers as well..

[RoyNBarlow]

In which course did we supposedly learn about the meaning of "the principal square root"? I mean, I know what a square root is, but the term "principal square root" is new and it makes it feel like in this video, I missed out on something.

[AhmedMunye]

Lol I just finished my algebra class in university. This could have helped especcially during the last couple of weeks.
These videos are awesome salman, i recomend you keep on the same path.

[jandy]

Imaginary/complex numbers are tricky but simplifying the square root does help

[darkrozen]

At 2:07, Why does that equation not work? Would it not just give the negative solution to the square root?

[otherdistractions]

Thanks! How do I simplify i when its nested in a radical within a larger expression?

[xxcsyannaxx]

it is the same as 2i square root of 13 right?

[drummersantana]

extremely helpful! thanks so much khan academy!!!

[lmva]

i cannot believe how much hate there is on this video

[TeeMee]

in your annotations you should have made it clear that you meant *principle* root of sqrt(52). I was for ages trying to figure out why you couldnt do sqrt(-x-y) = sqrt(-x)sqrt(-y) when actually it's completely valid considering the negative solution.

[FahimusAlimus]

I tried that simplification of (-1)^0.5*(-52)^0.5 and it did equal (52)^0.5.

[favageseline]

Do you put plus or minus at the beginning of the final answer or do you keep it as is

[DarkSwarley]

Thanks so much, I always forget this kind of stuff

[fahmylina]

What is the value of (- zero)^0.50?  - - - - - this is a good question !!!, if the answer of (-1)^0.50 is "i", so the answer of (-zero)^0.50 is "we" - - - - -

[babycarrotz]

Would someone explain to me why you multipy 13 and 2 to get the squared?

[igobyharel]

Found shortcut: find the square root of the positive version of the number, and just multiply that by i. For example: square root of -9 is 3i. Square root of -25 is 5i. Square root of -4 is 2i.
This is pretty simple, idk why he over complicated it

[theophonchana]

Square root of 52 = 2 × square root of 13

[ctw]

This shit makes no sense, well looks like im dropping out to become a stripper! 

[theophonchana]

Square root of a negative number = error