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what's the modulus of -i? watch

1. ????

is it

i?

thanks

jb
2. What does the modulus of a complex number mean?
3. Modulus of -i is square root of ( -1^2), so it is 1. Remember you are trying to find the magnitude of the complex number.
Edit: Argument is -pi/4...
4. We tend to call it the magnitude rather than the modulus when dealing with complex numbers.

If , then it's magnitude is defined as .

We can write , so its magnitude is using the above formula.
5. (Original post by impervious)
Modulus of -i is square root of ( -1^2), so it is 1. Remember you are trying to find the magnitude of the complex number.
Argument is pi/2...

surely

the square root of -1 squared
is 1 or -1
(Original post by Dez)
We tend to call it the magnitude rather than the modulus when dealing with complex numbers.

If , then it's magnitude is defined as .

We can write , so its magnitude is using the above formula.

i've been taught that i squared is -1
and i cubed is 1
6. (Original post by impervious)
Modulus of -i is square root of ( -1^2), so it is 1. Remember you are trying to find the magnitude of the complex number.
Argument is pi/2...
Argument is -pi/2 or perhaps 3pi/2 depending on the range of arguments you're permitting
7. -i is the complex number: 0 - 1i

and the modulus will be the square root of 0^2 + (-1)^2

so the modulus will be 1.
8. (Original post by jumblebumble)

surely

the square root of -1 squared
is 1 or -1

i've been taught that i squared is -1
and i cubed is 1
i cubed is -i
9. (Original post by jumblebumble)

surely

the square root of -1 squared
is 1 or -1
You always take the positive square root for modulus
10. [QUOTE=jumblebumble]

surely

the square root of -1 squared
is 1 or -1
Its sqrt((-1)^2), so sqrt(1).

(Original post by RichE)
Argument is -pi/2 or perhaps 3pi/2 depending on the range of arguments you're permitting
You are half correct, but I was originally completely wrong

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