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# What does the little ‘i’ mean? watch

1. Anybody know what it means? It changed my negative square root to a simplified surd form with a little ‘i’ after the coefficient. What is it and why did it do that?
2. (Original post by Y11_Maths)
Anybody know what it means? It changed my negative square root to a simplified surd form with a little ‘i’ after the coefficient. What is it and why did it do that?
sqrt(-1) can't be evaluated to a real number.
So we make some new numbers to accomodate for this.
We make i = sqrt(-1)
and now you can do **** like writing 5+i or -3-9i.

eg. sqrt(-4) = sqrt(4)sqrt(-1) = 2i
3. (Original post by StayWoke)
sqrt(-1) can't be evaluated to a real number.
So we make some new numbers to accomodate for this.
We make i = sqrt(-1)
and now you can do **** like writing 5+i or -3-9i.

eg. sqrt(-4) = sqrt(4)sqrt(-1) = 2i
Ahh ok got it thanks
4. It is used to represents complex numbers. You can’t take the square root of a negative, thus i creates an imaginary number. i=sqrt(-1) and i2=1
5. 'i' is an imaginary number. If you've never heard of it before then you probably haven't been taught it so just ignore it.
6. Oooo imaginary numbers. I know someone else just explained it so I won’t bother repeating it. Imaginary numbers are cool 🤓

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Updated: February 7, 2018
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