Question

$\text{If}a=1+i,\text{then}{a}^2\text{equals}$

• A. 1 - i
• B. 2i
• C. (1 + i) (1 - i)
• D. i - 1

Answer 1

The correct option is B

2i

a = 1 + i

On squaring both the sides, we get,

$a^2=(1+i{)}^2\Rightarrow a^2=1+i^2+2i\Rightarrow a^2=1-1+2i(\because i^2=-1)\Rightarrow a^2=2i$