How do you find $abs( 8i )$ ?

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Answer 1 · 2016-06-22T00:18:13

$|8i| = 8$

The modulus of a complex number $a+bi$ , denoted $|a+bi|$ , represents that number's distance from the origin on the complex plane, and is given by

$|a+bi| = sqrt(a^2+b^2)$

Then, for our given number, we have

$|8i| = |0+8i| = sqrt(0^2+8^2) = sqrt(64) = 8$

Note that this is as intuition tells us, as $8i$ is $8$ units from the origin along the imaginary axis on the complex plane.

How do you find abs( 8i )abs( 8i )?