Modulus of z1 z2 where z1 and z2 are complex:
A|z1| + |z2|
B|z1|/|z2|
C|z1| - |z2|
D|z1| × |z2|
Answer & Solution
Correct answer: D. |z1| × |z2|
Important property: |z1 z2| = |z1| × |z2|. Modulus is multiplicative. (Also |z1/z2| = |z1|/|z2| when z2 ≠ 0.)
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