Question

a) (2-i)(4+i)= ?
c) (1+i) totul la a2-a= ?
e) (1-i) totul la a4-a= ?

Answer 1

a) =8+2i-4i-i²
=8--2i-i²           inmultim -1
=i²+2i-8

c)=1+2i+i²

e)=[(1-i)²]²
=(1-2i+i²)²
=(1-2i+i²)(1-2i+i²)
=1-2i+i²-2i+4i²+2i³+i³-2i³+i⁴
=i⁴+3i³+5i²-4i+1