Friday, September 15, 2017

Where did I get that idea???  Well to complete the square root function..........to the West of 0.......in the negative numbers.........if u had the regular X and Y axis of the Cartesian plane...........where would u put the square root of - 1........which is what i is.............????



Imaginary Numbers


An Imaginary Number, when squared, gives a negative result.
imaginary squared => negative

Try

Let's try squaring some numbers to see if we can get a negative result:
No luck! Always positive, or zero.
It seems like we cannot multiply a number by itself to get a negative answer ...
thought... but imagine that there is such a number (call it i for imaginary) that could do this:
i × i = −1
Would it be useful, and what could we do with it?
Well, by taking the square root of both sides we get this:
equals the square root of -1
Which means that i is the answer to the square root of −1.
Which is actually very useful because ...
... by simply accepting that i exists we can solve things
that need the square root of a negative number.
Let us have a go:

Example: What is the square root of −9 ?

Answer: = √(9 × −1) = √(9) × √(−1) = 3 × √(−1) = 3i
(see how to simplify square roots)
Hey! that was interesting! The square root of −9 is simply the square root of +9, times i.
In general:
√(−x) = i√x
So long as we keep that little "i" there to remind us that we still
need to multiply by √−1 we are safe to continue with our solution!
Using i we can also come up with new solutions:

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