How do you find $| - 3 i |$ $abs( -3 i )$ ?

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Answer 1 · 2016-10-27T01:42:57

$| - 3 i | = 3$ $abs(-3i) =3$

The absolute value of a number is its distance from the origin,
So if we take our complex number with cartesian coordinates,

$(0, - 3)$ $(0,-3)$ or $0 - 3 i$ $0-3i$

to work out its distance we use Pythagoras's theorem.

$c^{2} = a^{2} + b^{2}$ $c^2=a^2+b^2$

with $c = | (a , b)) |$ $c=abs(("a , b)")$

so to find out c,

$c = \sqrt{a^{2} + b^{2}}$ $c=sqrt(a^2+b^2)$

$c = \sqrt{{(0)}^{2} + {(- 3)}^{2}}$ $c=sqrt((0)^2+(-3)^2)$

$c = \sqrt{9}$ $c=sqrt(9)$

$c = 3$ $c=3$

$| - 3 i | = 3$ $abs(-3i) =3$

How do you find |−3i|abs( -3 i )?