Question

Below
(3 - i)(3 + 1) =

Answer 1

12-4i

Explanation:

i means √-1

(3 - i)(3 + 1) =

3*3=9

3*1=3

-i*3= -3i

-i*1 = -i

9+3-3i-i=

12-4i <--- answer

(3 - i)(3 + i) =

3*3=9

3*i=3i

-i*3= -3i

-i*i = -(√-1)*(√-1) = -(-1) = 1

9+3i-3i+1 =

10 <--- answer