Answer:
12-4i
Step-by-step 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*i=3i
-i*i = -(√-1)*(√-1) = -(-1) = 1
9+3i-3i+1 =
10 <--- answer
