Question

The value of $(1-i{)}^4$ is

• A. $4$
• B. $-4$
• C. $4i$
• D. $-4i$

Answer 1

The correct option is B $-4$

$(1-i{)}^4=(1-i{)}^2(1-i{)}^2$
$=(1+i^2-2i)(1+i^2-2i)$
$=(-2i)(-2i)$
$=4i^2=-4,[\because i^2=-1]$